The answer for the first question is A) Scientists have lots of evidence to explain why dragons don't exist.
Reason: The reason why this answer is right is because scientists explained that "They laughed at the idea of dragons breathing fire", that it would be impossible for the dragons to fly up because they were too big (fat).
The answer for the second question is C) I have always wondered if dragons existed, and I hope they did.
Reason: She was wondering if the dragons ever existed because of the fact that scientists were judging that there was no such thing as dragons, while other people think that there is such things as dragons (like for instance, they appeared in legal papers, the Bible, even the Chinese calender.
Assuming this question is asking for a definition/synonym/"other word" for chivalrous, the answer is courteous. leaving a more comfortable seat for an elderly person is a respectful and polite gesture, which shows courtesy.
