It is up to you !!!

John : Would you like to go out to dinner or to a movie ?

Karen : Either one, it is up to you .

John : What would you prefer ?

Karen : I really don't care, I just want to get out of the house.

John : Well, then how about dinner and a movie ?

Karen : That's a great idea !

Explanation :

If you say that it is up to someone to do something, you mean that it is their responsibility to do it.