The correct answer is B.

This is a one-user exception. Salesforce recommends using permission sets to extend access without changing the user’s base profile. A permission set can grant read-only field access through field-level security to just the selected customer service agent. Salesforce documentation explains that permission sets extend user access, and field permissions control whether users can view or edit individual fields.

Why others are incorrect:

A creates a new profile for one user, which is not the recommended scalable solution.

C is not accurate because field-level security is assigned through profiles or permission sets, not directly to one user from the field alone.

D would give all users with the Customer Service profile read-only access, not only the single agent.

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