The requirement points to a specific Salesforce control. The proper configuration is D. Rich text area. In Salesforce terms, this is a record sharing targets issue. Manual record sharing can grant access to individual users, public groups, and roles with subordinates. It is a record-level access mechanism, separate from field- level security and permission set assignment.
The selected configuration is the professional answer because it is native, declarative, and placed at the right scope. If the requirement later expands, another administrator can inspect the same metadata area and understand how the behavior is being produced. That is far better than a solution that depends on hidden assumptions or user training.
The wrong answers confuse adjacent platform concepts. A (URL) is only a partial match because it does not provide the same direct administrative control as the selected option. B (Multi-select picklist) misses the mark because That field type either stores the wrong kind of value or fails to support the required behavior as cleanly as the selected option. C (Long text area) is not enough: That field type either stores the wrong kind of value or fails to support the required behavior as cleanly as the selected option. This keeps the build declarative, traceable in Setup, and easier to support when the org changes later.
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