Microsoft Updated AI-900 Exam Questions and Answers by advik

Azure Custom Vision is a cognitive service that lets you build, deploy, and improve your own image classifiers. An image classifier is an AI service that applies labels (which represent classes) to images, according to their visual characteristics. Unlike the Computer Vision service, Custom Vision allows you to specify the labels to apply.

Note: The Custom Vision service uses a machine learning algorithm to apply labels to images. You, the developer, must submit groups of images that feature and lack the characteristics in question. You label the images yourself at the time of submission. Then the algorithm trains to this data and calculates its own accuracy by testing itself on those same images. Once the algorithm is trained, you can test, retrain, and eventually use it to classify new images according to the needs of your app. You can also export the model itself for offline use.

Full Detailed Explanation (250–300 words):

“You can fine-tune some Azure OpenAI models by using your own data.” – YESThis statement is true. Azure OpenAI allows customers to fine-tune certain models like GPT-3, GPT-3.5, and some embedding models with their own data. Fine-tuning customizes a model to perform better on specific tasks or match a company’s domain terminology, tone, or context. According to Microsoft Learn’s AI-900 and Azure OpenAI documentation, fine-tuning is supported for approved use cases while maintaining Microsoft’s Responsible AI oversight and compliance process.

“Pretrained generative AI models are a component of Azure OpenAI.” – YESThis statement is also true. Azure OpenAI provides access to pretrained large language and generative AI models such as GPT-3.5, GPT-4, Codex, and DALL·E. These models are pretrained on vast datasets and made available via APIs, allowing developers to generate text, code, and images without needing to train their own models. This is a core feature of Azure OpenAI’s service offering.

“To build a solution that complies with Microsoft responsible AI principles, you must build and train your own model.” – NOThis statement is false. Compliance with Microsoft Responsible AI principles (Fairness, Reliability & Safety, Privacy & Security, Inclusiveness, Transparency, Accountability) does not require building custom models. Prebuilt Azure AI and OpenAI services already align with Responsible AI standards. Developers simply need to use these services responsibly, applying governance and ethical design practices.

According to the Microsoft Azure AI Fundamentals (AI-900) official study guide and the Microsoft Learn module “Explore natural language processing (NLP) in Azure”, key phrase extraction is a core feature of the Azure AI Language Service that enables you to automatically identify the most important ideas or topics discussed in a body of text.

When analyzing customer feedback surveys, key phrase extraction helps summarize the main talking points or recurring themes by detecting significant words and phrases. For instance, if multiple customers write comments like “The checkout process is slow” or “Website speed could be improved,” the model may extract key phrases such as “checkout process” and “website speed.” This allows businesses to quickly understand the most common subjects without manually reading each response.

Let’s review the other options:

A. Language detection: Determines the language of the text (e.g., English, French, or Spanish) but does not identify main ideas.

B. Translation: Converts text from one language to another using Azure Translator; it does not summarize or extract key information.

C. Entity recognition: Identifies named entities such as people, organizations, locations, or dates. While useful for identifying specific details, it does not capture general topics or overall discussion points.

Therefore, the appropriate NLP feature for identifying main topics or themes within textual data such as survey responses is Key Phrase Extraction.

This capability is part of the Azure AI Language Service and is commonly used in sentiment analysis pipelines, customer feedback analytics, and business intelligence workflows to summarize large text datasets efficiently.

According to the Microsoft Azure AI Fundamentals (AI-900) official study guide and the Microsoft Learn module “Prepare data for machine learning”, feature engineering refers to the process of transforming raw data into meaningful features that can be effectively used by machine learning algorithms. This includes steps such as scaling, normalization, encoding categorical variables, handling missing values, and creating new features derived from existing ones.

The question states:

“Ensuring that the numeric variables in training data are on a similar scale.”

This directly describes a data normalization or standardization step, which is a core component of feature engineering. The purpose of scaling numeric variables is to ensure that all features contribute equally to the model’s learning process. Without normalization, features with large numeric ranges (such as “income in dollars”) could dominate smaller-scale features (like “age in years”), leading to biased model performance.

In Azure Machine Learning, this is typically done using the Normalize Data module or transformations in the data preparation stage. Microsoft Learn explains that normalization and feature scaling are applied before model training to ensure that gradient-based algorithms (such as regression or neural networks) converge more efficiently and produce more accurate results.

The other options are not correct:

Data ingestion refers to collecting and importing data into a system.

Feature selection involves choosing the most relevant features, not scaling them.

Model training is the phase where the algorithm learns patterns from the processed data, which occurs after feature engineering.

Therefore, ensuring that numeric variables are on a similar scale is a step in Feature Engineering.