This is a principle question that asks us to identify, from the available answer choices, a principle that would strengthen the conclusion in the stimulus. So let's first be sure that we understand the stimulus correctly.
In the stimulus, the counselor concludes that Hagerle owes him a sincere apology. There are two premises given in support of this conclusion:
Premise: Hagerle sincerely apologized to the physician for lying to her.
Premise: Hagerle told me (the counselor) the same lie.
As you can see, neither of those premises is enough to support the counselor's conclusion that Hagerle owes him a sincere apology, too.
Now let's examine each of the possible answer choices and evaluate whether one of them would, in fact, justify the conclusion.
Answer choice (A) doesn't go far enough. Just because it's "good" to apologize for having done something wrong to a person if one is capable of doing so sincerely does not necessarily mean that Hagerle "owes" the counselor an apology.
Answer choice (B) is also insufficient to justify the conclusion. We do not know that BOTH the counselor and the physician were, in fact, owed an apology.
Answer choice (C), if added to the stimulus, would in fact justify the conclusion of the stimulus. If it is true that someone is owed a sincere apology for having been lied to by a person if someone else (here, the physician) has already received a sincere apology for the same lie from that same person, then the conclusion in the stimulus is justified.
Answer choice (D) can be eliminated because capability alone does not justify the counselor's conclusion that he is also owed an apology. Put differently, if (D) alone were enough, then it wouldn't matter that Hagerle had also made an apology to the physician, right?
Notice how answer choice (E) does not talk about when an apology is OWED, which is what the conclusion in the stimulus is about. Rather, answer choice (E) discusses when a person ought to apologize ("should"). That's not the same thing.
Hope this helps! Please let us know if you have any additional questions.
