If someone asks you to do something, and you don't want to do it "No" is a perfectly acceptable answer. You don't owe anyone an explanation or worse a rationalization for your decision not to participate/do whatever someone else wants you to do.
This is of course assuming you are not 4 and your parents are asking you to clean your room. lol.
This is of course assuming you are not 4 and your parents are asking you to clean your room. lol.