I cast the vote for the art history class. Especially if you have never taken any classes that are about art before. Art and history are so incredibly intertwined that it is impossible to study one without the other. It is a subject that someone could spend their entire life on and not run out of interesting things to investigate.
An AP art history class will be a great introduction. It could change the way that you look at the world and give you the impetus to want to learn more. In many cases it is the art that tells us what was going on in the past. This is true for ancient civilizations and it is fascinating. The study of history can be so dry but when you are looking at objects of art, it gives you a whole new perspective and slows down human history to just a short period of time to when that artifact was created and all about it.
Unfortunately art is not considered as important as it was in the past. With budget cuts it is one of the first things to go. learning about art history gives art another chance. It gives people a look at what it can mean to a society and is worthy of study.