1. What evidence supports the common ancestry of humans and chimpanzees?

Evolution? i think.

I do agree with that, scientists claim that evolution was how Homo sapiens branched off of the genus Homo. There is evidence to evolution, though.

The first is a cladogram, which shows evolutionary relatedness based on ancestral traits and derived traits. So bones and teeth for the ancestral. That would definitely show relatedness between humans and chimpanzees.

The next is a fossil, which is used to identify organisms and place them on cladograms.