Please help... question about T2i

Hi, I am finding that a lot of my pictures are very soft and/or out of focus, i have a canon T2i.

I was wondering if it is possible that something is wrong with the camera body that would affect the auto focus. Or is autofocus solely determined by the lens? i just did a test this weekend and rented the best canon lenses possible, the 24-70 and the 50 1.2 and still i am having issues with soft images! I would really like to find out what the problem could possibly be, and if needed want to service the camera body.

The camera has been dropped... would this affect the auto focus function?