Whichever your friends or family know best (or lacking that, whichever you find the most readable / enjoyable documentation for).

You can't really go wrong with either of the mainstream languages, so I'd advise you to have a look at the documentation or tutorials for some of them, and choose one that you like best.

It also depends a lot on what you want to write, as certain languages are better for one task than the other. I wouldn't write a web app in C, for example, nor would I write an operating system kernel in python.