You are a business analyst deciding which output-formatting and context-window practices to recommend to teammates.

Answers D and E are correct. Trimming irrelevant material keeps the context concentrated on information that can influence the requested result. This reduces distraction, avoids wasting context capacity, and lowers the chance that stale or unrelated content will compete with authoritative sources. Clear section headers separate instructions, source material, examples, and task inputs, helping Claude distinguish their functions and attribute claims correctly. Anthropic’s prompting guidance recommends structured long-context inputs and descriptive XML tags for exactly this reason: explicit boundaries reduce ambiguity when a prompt contains multiple content types or documents. Option A is unsafe as a general practice because reusing an unchanged context block can carry obsolete facts or irrelevant constraints into a new request. Option B indiscriminately includes complete email threads, creating noise and potentially unnecessary personal or confidential data. Option C removes all source boundaries, making attribution and instruction following harder. Although Anthropic also recommends placing long-form documents before the query in large-context prompts, placement cannot compensate for poor curation or missing structure. Effective context management therefore has two complementary parts: select only relevant material and organize that material into clearly labelled sections. D performs the curation step, while E supplies the structure needed for reliable interpretation. Anthropic long-context prompting guidance

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