Answer:
D, Conducting investigations of wrongdoings.
Explanation:
An ethics officer has the responsibility of developing and supervising the ethics of an organisation.
The develpment and supervising of ethics ranges from maintaining professional ethisc or industry ethics or implementation of an a compliance program, development of a compliance program as well as other option listed in the question.
Conducting investigations is not one of the most important responsibilities of an ethics officer and thus ranks lowest.
Cheers.