This would be the hardest question ever... But my current favourite is this:

Adam is talking to God and says:

"Thank you for putting Eve on earth for me, please tell me why you made her skin so smooth"

God: "So that you will want to hold her against you always"

Adam: "Ah, and please tell me why you made her smell so nice?"

God: "So that you will always be drawn near to her"

Adam: "I see, I really appreciate that and don't mean to seem ungrateful but why did you make her so stupid"

God: "That is the easiest one to answer - I did that so that she would love you!"