This is a governance decision before it is a configuration click. The proper configuration is C. App Manager.
The requirement in the stem is: Where can an app builder edit an existing app to add Components to the utility bar? The selected option addresses that requirement at the point where Salesforce actually evaluates the behavior.
The underlying concept is Lightning page configuration. Lightning App Builder controls page composition, component visibility, activation, assignments, and specialized surfaces such as record pages, home pages, and utility bars. That is why this answer is more defensible than a workaround. It can be reviewed in Setup, included in the correct deployment path, and tested by impersonating or logging in as a representative user where appropriate.
The rejected choices solve different problems. A (Lightning App Builder) is less defensible because A Lightning component changes the interface; it does not automatically solve security, relationship, or data- quality requirements. B (Lightning Record Page) should be rejected because A Lightning component changes the interface; it does not automatically solve security, relationship, or data-quality requirements. D (App Menu) does not fit cleanly; it solves a symptom of the problem rather than the Salesforce mechanism that owns the result. The configuration remains understandable for future admins because the decision is visible in metadata rather than buried in a workaround.
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