How is dna used as evidence for evolution? a. all species have the same genetic code. b. all species have the same number of genes. c. all species have the same amount of dna. d. all species have the same genes.

I think it is the first one (or the last one, i am not sure I understand the statements), but the point is that all species have the same gene code for the same proteins and amino acides, for example the aminoacid Cytosine is encoded the same in all species

No because the eaeht is on a 23.5 degree axis tilt and so when it is winter the northern hemisphere is pointing away from the sun and the soutubern hemisphere is pointing toward the sun