Anti-supported; the author isn’t uncertain about whether the oath’s fundamental moral rules still apply today. The author believes the core value of beneficence still applies. To it wouldn’t make sense for the main point to involve an attempt to try to be certain about whether the oath’s moral rules still apply today.

This best captures the author’s view.

Although the author does agree with (C), it’s too broad to be the main point. The author’s message concerns a specific code of ethics — the Hippocratic oath. The author argues for retaining a core principle of the oath while allowing for minor adaptations of the oath. (C) expresses the general idea that codes of ethics developed for one society can be useful for later societies, but it doesn’t capture the author’s particular point about the Hippocratic oath.

This is too narrow to be the main point. The patients’ need for assurance and how it cannot be negated is simply one minor point in support of the view that the oath does not require a drastic overhaul or abandonment.

Anti-supported, because the author wants to retain the Hippocratic oath.