I believe it is c. Sentence 4 because it states that Chimpanzees use leaves. It introduces key details to support that claim. It also asks where the second major detail in the paragraph is introduced.I hope this helped and im not sure that this is the correct answer but i believe so.
I say A. BC he refused all.
Answer:
The princess wore a nice necklace round her smooth neck and she had a beautiful tiara on her head
For anyone looking back on this for answers; it's 'the fact that the passage begins with the transitional phrase "most importantly"'.