Answer:
The central Idea is "For many reasons, notable people sometimes avoid revealing their private identity".
Explanation:
If you read the text the author clearly expresses his/her feeling based on that one topic. The main idea is implied. (are those multiple answers or a text I'm not sure)
The appropriate response is compound subject. A compound subject is a subject comprised of at least two straightforward subjects that are joined by a planning conjunction and that have a similar predicate. sentence may have more than one straightforward subject or basic predicate. A compound subject is at least two basic subjects that have a similar predicate.
The flooding of the banks of the Mississippi river precluded the delta queen's docking on schedule. Hope this helps :)
Is it an oxymoron? Not sure if this is what you are looking for