What is an open-ended question?

a. one that's used to ask for clarification

b. one that requires either a yes or no answer

c. one that does not have a specific response

d. one that's meant to trick the speaker?

C. An open-ended question is something that someone can't usually say Yes or No to. It requires and descriptive answer.

Say I'd ask you "can you tell me something about yourself?" You give me a detailed answer opposed to me asking you "do you want to go here?"