Under Which of the Following Circumstances Is a Subordinate Lawyer

Under which of the following circumstances is a subordinate lawyer not in violation of the Model Rules?

A) If the subordinate lawyer calls the bar association's ethics hotline and follows the advice given by the ethics hotline.
B) If the subordinate lawyer reviews the Model Rules and state ethics opinions and reaches a reasonable resolution of an arguable ethical duty.
C) If the subordinate lawyer's supervisor calls the bar association's ethics hotline and follows the advice given by the ethics hotline.
D) If the subordinate lawyer's supervisor reasonably resolves an arguable issue of ethical duty and the subordinate lawyer acts according to the supervisor's resolution.