Answer:
Option D.The author's attitude toward a subject.
Explanation:

Answer: The way the reader knew that the flower girl was intelligent is that:
A) She is smart enough to know what things cost and how a gentleman should treat a guest.
Explanation: The dialect of the flower girl is not a criteria for intelligence but since she could effectively know the cost of things and how a gentleman should treat a guest, she could be attributed as an intelligent person.
This statement is an opinion because its subjective. some soldiers have seen or experienced terrible things which haunt their dreams and challenge their life in a way no gesture could mend. there are plenty of other soldiers who don't experience or see this though who are entitled to the same things as a gesture for their potential sacrifice.