Who do you think is the youngest?

Question

Who do you think is the youngest?

Answer 1

what kind of question is this?  Please clarify before I give you a better answer.  Otherwise, I'll only get 2 points instead of 10.

Answer 2

I am the youngest in my family.

Answer 3

Both my kids are younger than I am.

Answer 4

I think that an 18 year old is youngest!