This is a governance decision before it is a configuration click. A Lightning component must be exposed for the surface where it is used. A component built for one page type or action surface does not automatically become available everywhere in Lightning Experience. The correct response is therefore B. Edit a record page using Lightning App Builder > Drag the component onto the page.
The scenario is not asking for a feature list. It is asking which configuration produces the requested result with the fewest moving parts. A Salesforce app builder should favor a standard, visible Setup configuration whenever it fully meets the business need. That approach makes the build easier to validate in sandbox and easier to explain during release review.
The rejected choices solve different problems. A (Edit a record page using the Page Layout editor > Drag the Visualforce component onto the page.) is less defensible because Page layouts affect presentation; they do not grant the underlying object or field capability by themselves. C (Edit a record page using App Manager > Drag the component onto the page.) would be fragile here because A Lightning component changes the interface; it does not automatically solve security, relationship, or data-quality requirements. D (Edit a record page using the Page Layout editor > Drag the component onto the page.) does not fit cleanly; Page layouts affect presentation; they do not grant the underlying object or field capability by themselves. The configuration remains understandable for future admins because the decision is visible in metadata rather than buried in a workaround.
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