AI-900 Exam Dumps - Microsoft Certified: Azure AI Fundamentals Questions and Answers

When training a machine learning model, it is standard practice to randomly split the dataset into training and testing subsets. The purpose of this is to evaluate how well the model generalizes to unseen data. According to the AI-900 study guide and Microsoft Learn module “Split data for training and evaluation”, this ensures that the model is trained on one portion of the data (training set) and evaluated on another (test or validation set).

The correct answer is C. to test the model by using data that was not used to train the model.

Random splitting prevents data leakage and overfitting, which occur when a model memorizes patterns from the training data instead of learning generalizable relationships. By testing on unseen data, developers can assess true performance, ensuring that predictions will be accurate on future, real-world data.

Options A and B are incorrect because:

A. Train the model twice does not improve accuracy; model accuracy depends on data quality, feature engineering, and algorithm choice.

B. Train multiple models simultaneously refers to model comparison, not the purpose of splitting data.

Thus, the correct reasoning is that random splitting provides a reliable estimate of the model’s predictive power on new data.

According to the Microsoft Azure AI Fundamentals (AI-900) Official Study Guide and the Microsoft Learn module “Explore fundamental principles of machine learning,” anomaly detection is a specialized machine learning technique used to identify data points, patterns, or events that deviate significantly from normal behavior.

Anomaly detection is widely used for monitoring time-series data and detecting unexpected or rare occurrences that may indicate problems, opportunities, or fraud. For example:

Detecting fraudulent transactions in banking systems.

Identifying equipment malfunctions in industrial IoT applications.

Monitoring network intrusions in cybersecurity.

Detecting unexpected spikes or drops in web traffic or sales.

In Azure, this workload is supported by the Azure AI Anomaly Detector service, which uses statistical and machine learning algorithms to learn from historical data and establish a baseline of normal behavior. When the system detects data points that fall outside expected patterns, it flags them as anomalies.

Let’s evaluate the incorrect options:

A. A machine learning technique that understands written and spoken language → This describes Natural Language Processing (NLP), not anomaly detection.

B. A machine learning technique that classifies objects based on user-supplied images → This refers to image classification, typically using computer vision.

D. A machine learning technique that classifies images based on their contents → Also describes computer vision, not anomaly detection.

Therefore, the correct answer is C, since anomaly detection specifically refers to analyzing data over time and identifying unusual or abnormal patterns that differ from the expected trend.

The Azure AI Vision service (formerly Computer Vision) is designed to analyze visual content in images and videos. According to Microsoft Learn’s “Describe features of computer vision workloads,” Azure AI Vision can identify objects, people, text, and scenes, and even classify images or detect objects in real time.

Identifying breeds of animals in live video streams is an example of image classification or object detection—core capabilities of Azure AI Vision. The Vision service can analyze each frame in a video, recognize animals, and classify them according to known categories, making this the correct answer.

The other options are incorrect:

B. Extracting key phrases from documents → Done by Azure AI Language (Text Analytics).

C. Extracting data from handwritten letters → Done by Azure AI Document Intelligence (Form Recognizer) using OCR.

D. Creating thumbnails for training videos → While possible in Azure Media Services, it’s not a primary Azure AI Vision function.

Thus, the best answer is A. Identifying breeds of animals in live video streams.

This question evaluates understanding of fundamental machine learning concepts as covered in the Microsoft Azure AI Fundamentals (AI-900) official study guide and Microsoft Learn module “Explore the machine learning process.” These statements relate to data labeling, model evaluation practices, and performance metrics—three essential parts of building and assessing a machine learning model.

Labelling is the process of tagging training data with known values → YesAccording to Microsoft Learn, “Labeling is the process of tagging data with the correct output value so the model can learn relationships between inputs and outputs.” This is essential for supervised learning, where models require historical data with known outcomes. For example, if training a model to recognize fruit images, each image is labeled as “apple,” “banana,” or “orange.” Hence, this statement is true.

You should evaluate a model by using the same data used to train the model → NoThe AI-900 guide stresses that using the same data for both training and evaluation can cause overfitting, where the model performs well on training data but poorly on unseen data. Instead, the dataset is split into training and testing (or validation) subsets. Evaluation must use test data that the model has never seen before to ensure an unbiased measure of performance. Therefore, this statement is false.

Accuracy is always the primary metric used to measure a model’s performance → NoMicrosoft Learn emphasizes that accuracy is only one metric and not always the best choice. Depending on the problem type, other metrics such as precision, recall, F1-score, or AUC (Area Under the Curve) may be more appropriate—especially in cases with imbalanced datasets. For example, in fraud detection, recall may be more important than accuracy. Thus, this statement is false.

In Azure OpenAI Service, the temperature parameter directly controls the creativity and determinism of responses generated by models such as GPT-3.5. According to the Microsoft Learn documentation for Azure OpenAI models, temperature is a numeric value (typically between 0.0 and 2.0) that determines how “random” or “deterministic” the output should be.

A lower temperature value (for example, 0 or 0.2) makes the model’s responses more deterministic, meaning the same prompt consistently produces nearly identical outputs.

A higher temperature value (for example, 0.8 or 1.0) encourages creativity and variety, causing the model to generate different phrasing or interpretations each time it responds.

When a question specifies the need for more deterministic responses, Microsoft’s guidance is to decrease the temperature parameter. This adjustment makes the model focus on the most probable tokens (words) rather than exploring less likely options, improving reliability and consistency—ideal for business or technical applications where consistent answers are essential.

The other parameters serve different purposes:

Frequency penalty reduces repetition of the same phrases but does not control randomness.

Max response (max tokens) limits the maximum length of the generated output.

Stop sequence defines specific tokens that tell the model when to stop generating text.

Thus, the correct and Microsoft-verified completion is:

“You can modify the Temperature parameter to produce more deterministic responses from a chat solution that uses the Azure OpenAI GPT-3.5 model.”

The correct answers are B. Azure REST API and C. Azure SDK for Python.

The Azure OpenAI Service can be accessed using multiple development interfaces. According to Microsoft Learn documentation, developers can call the service via the Azure REST API, which provides direct HTTPS-based access to the model endpoints for tasks like completions, chat, embeddings, and image generation. This interface is platform-independent and supports integration with any system capable of making HTTP requests.

Additionally, Azure SDKs offer higher-level libraries for convenient integration into applications. The Azure SDK for Python and Azure SDK for JavaScript are both supported for Azure OpenAI interaction, allowing developers to authenticate with Azure credentials, send prompts, and receive model responses programmatically.

However, among the listed options, the REST API (B) and SDK for Python (C) are most explicitly referenced in the AI-900 learning modules and Microsoft documentation as standard tools to call Azure OpenAI services.

Option A (Azure CLI) is incorrect because the CLI is used primarily for provisioning and managing Azure resources, not for directly calling OpenAI model endpoints.

Therefore, based on the Azure AI-900 and OpenAI integration guidance, the correct answers are B. Azure REST API and C. Azure SDK for Python.

The correct completion of the sentence is:

“You can use the Custom Vision service to train an object detection model by using your own images.”

According to the Microsoft Azure AI Fundamentals (AI-900) official study guide and Microsoft Learn module “Identify features of computer vision workloads,” the Azure Custom Vision service is a specialized component of Azure Cognitive Services for Vision that enables developers to train custom image classification or object detection models using their own labeled image datasets.

The Custom Vision service differs from the Computer Vision service in that it allows full customization — meaning you can upload your own images, tag them manually, and train the model to recognize objects specific to your use case (for example, detecting your company’s products, tools, or vehicles). Once trained, the model can identify and localize these objects in new images by returning bounding boxes and confidence scores, which is precisely what defines an object detection workload.

Microsoft’s AI-900 materials describe object detection as the process of identifying objects in an image and determining their position, typically represented by bounding boxes. Custom Vision supports two main project types:

Image Classification: Determines what is present in the image (e.g., “dog,” “cat,” “car”).

Object Detection: Identifies what is present and where it is located in the image.

In contrast:

Computer Vision provides prebuilt models for general image analysis but doesn’t allow custom model training.

Form Recognizer is used for extracting text and data from structured or semi-structured documents.

Azure Video Analyzer for Media focuses on video content analysis, not custom object detection.

Therefore, based on the official Microsoft AI-900 study guide and Microsoft Learn content, the verified and correct answer is Custom Vision, as it specifically allows training of a custom object detection model using your own images.

Object detection is similar to tagging, but the API returns the bounding box coordinates for each tag applied. For example, if an image contains a dog, cat and person, the Detect operation will list those objects together with their coordinates in the image.

The question describes a smart device that can understand and respond to a spoken or written question such as, “What is the stock price of Contoso, Ltd.?” This scenario directly maps to the Natural Language Processing (NLP) workload in Microsoft Azure AI.

According to the Microsoft AI Fundamentals (AI-900) study guide and the Microsoft Learn module “Describe features of common AI workloads,” NLP enables systems to understand, interpret, and generate human language. Azure AI Language and Azure Speech services are examples of NLP-based solutions.

In this case, the smart device performs several NLP tasks:

Speech recognition – converts spoken input into text.

Language understanding – interprets the user’s intent, i.e., retrieving the stock price of a specific company.

Response generation – formulates a meaningful answer that can be presented back as text or speech.

This process shows a full pipeline of natural language understanding (NLU) and conversational AI. It does not involve visual data (computer vision), data pattern analysis (anomaly detection), or document search (knowledge mining).

Hence, the correct AI workload is D. Natural Language Processing.

According to the Microsoft Azure AI Fundamentals (AI-900) official study guide and the Microsoft Learn module “Describe features of natural language processing (NLP) workloads on Azure,” Natural Language Processing refers to the branch of AI that enables computers to interpret, understand, and generate human language. One of the main NLP workloads identified by Microsoft is speech-to-text conversion, which transforms spoken words into written text.

Creating a text transcript of a voice recording perfectly fits this definition because it involves converting audio language data into text form — a process handled by speech recognition models. These models analyze the acoustic features of human speech, segment phonemes, identify words, and produce a text transcript. On Azure, this function is implemented using the Azure Cognitive Services Speech-to-Text API, part of the Language and Speech services.

Let’s examine the other options to clarify why they are incorrect:

Computer vision workload: Involves interpreting and analyzing visual data such as images and videos (e.g., object detection, facial recognition). It does not deal with speech or audio.

Knowledge mining workload: Refers to extracting useful information from large amounts of structured and unstructured data using services like Azure Cognitive Search, not transcribing audio.

Anomaly detection workload: Involves identifying unusual patterns in data (e.g., fraud detection or sensor anomalies), unrelated to language or speech.

In summary, when a system creates a text transcript from spoken audio, it is performing a speech recognition task—classified under Natural Language Processing (NLP). This workload helps make spoken content searchable, analyzable, and accessible, aligning with Microsoft’s Responsible AI goal of enhancing accessibility through language understanding.