69.
The answer is: D
Explanation
The correct option is D: A has a professional obligation to act solely on the instructions of the client, C, and should not withdraw the suit on B's instructions.
Explanation:
According to the principle, an advocate has a duty to act only on the instruction of the client, and no one else. Therefore, A cannot withdraw the suit filed by C without C's consent, even if B is C's mother and is concerned about the family reputation. A has to respect C's autonomy and decision as the client, and cannot act on the basis of B's wishes or interests. The other options are incorrect because they either ignore or violate the principle of acting only on the client's instruction.