scuba diving or skydiving?

Which one do you prefer (or if you have not done either, which one would you like to do the most?)

For me, it would definitely be scuba diving.  First of all, I am scared of heights and I would have a really difficult time jumping out of an airplane.  Scuba diving seems beautiful.  Not only do you get to see the lush underground environment, but you can spend some quality time alone or in a group.