Which detail best supports this central idea?

thomas more’s utopia was written as a social critique.

“utopia” is a greek word that means “no place.”

an emphasis on nutrition would be important in this society.

everyone has a different idea about a perfect society.

I had to look to see if I could find what the central idea was that this question is asking about. If it is - In my own personal utopia, health and nature would be top priorities, then the answer would be the third option an emphasis on nutrition would be important in this society. Thomas More is talking about how health and nature would be very important in his own idea of a personal utopia, therefore he is talking about nutrition.  

the main character of "the secret life of walter mitty" retreats into a false pretense as a means escape from his mundane reality -- this is a flagrant issue seen in societies abroad, typically found in young adults and it is robbing our youths of their childhood.

explanation:

a thesis -- a well developed, formal thesis is required to be one sentence long. there are many themes in "the secret life of walter mitty" and i had resolved to give you one of the simpler ones while still honing it with class.