Exact extracts:
* "In supported IDEs, you can ask Copilot Chat to explain code or suggest improvements." References: GitHub Copilot Chat IDE integration documentation.

"Fill-in-the-Middle (FIM) enables Copilot to consider both prefix and suffix code, generating more accurate suggestions for the missing middle portion." This makes option D correct, as it explains how FIM enhances suggestion accuracy.
References: GitHub Copilot model training and FIM technique documentation.

The quality of Copilot's suggestions is enhanced by clearly defining the task, using meaningful variable names, and providing examples of the desired output.

The duplication detection filter can be configured at the organization level to prevent GitHub Copilot from suggesting publicly available code snippets.

"GitHub Copilot may sometimes suggest deprecated code, APIs, or patterns if these appear in its training data. Users are responsible for reviewing and updating the suggestions." This confirms that Copilot does not automatically update or reject deprecated features, but may still suggest them if they were part of training.
References: GitHub Copilot usage limitations documentation.