Rephrasing the question:
5. What evidence is there for evolution?
Firstly there's the fossil evidence--not the existence of fossils of course, since that only proves that creatures have become extinct in the past; since creatures are going extinct in the present with monotonous regularity that should come as no surprise. Prior to the theory of evolution, it was possible to collect life-forms together into related groups--giraffes being more closely related to okapis than to pigs for example. The theory of evolution suggested that the remains of creatures which might naturally seem like ancestors of closely related creatures should be found in relatively recent geological strata, and that those of theoretical ancestors to less closely related species would be found in more ancient geological strata. This is, in fact, what the fossil record reveals.
Secondly there's the evidence of DNA analysis (something that wasn't available when I was first learning about this). Examining the differences in DNA of related species we're able to identify DNA markers, identical in all of one species, and identically different in all members of another. Using rates of mutation and ratios of successful to fatal mutations, scientists can perform a statistical analysis on the nearby genes (representing neutral mutations--genetic variety--hair-color etc.) and conclude when the two species might have been the same. The answers agree with the fossil record where available. Not only that, they agree when the analysis is performed using different marker genes. And they agree over all species that have been analyzed in this way.
Thirdly, the theory of evolution predicts that useful mutations might continue, even if they carry anomalous side-effects (side-effects that one might expect to see corrected if design were true). Such side-effects are seen in "junk DNA" where species still carry the dormant DNA strands for functions no longer of any use to them--gills encoded, but no longer expressed, in land animals for example. Similarly, the giraffe has a nerve going from its throat to its brain which travels all the way down the neck, round the shoulders and back up again--a natural side-effect of increasing neck-length, but rather an odd design feature. And all vertebrates have eyes that are constructed backwards, while invertebrates have the better, right-way-out design (hence the blind spot), suggesting that the eye evolved sometime after the backbone did.