Explanation

Source Attribution in Knowledge Bases for Bedrock is the correct answer because:

• Source Attribution is a built-in feature specifically designed for Amazon Bedrock Knowledge Bases that automatically cites the exact source documents used to generate AI responses
• This feature is essential for legal firms and other regulated industries that require traceability and verifiability of AI-generated content
• When Bedrock generates answers using knowledge bases, Source Attribution provides references to the specific documents, pages, or sections that were used to formulate the response
• Bedrock Guardrails (Option A) is a different feature focused on content filtering and safety controls, not source citation

This functionality helps legal professionals maintain compliance, verify accuracy, and ensure proper documentation of AI-assisted legal research and analysis.