A, D, and not sure but maybe E
Answer:they won't for a pair
Explanation:Basically it all depends on process called complementary base pairing, the structure of thymine and adenine is such that it forms two hydrogen bonds and therefore pair up
2.guanine and cytosine have such structure that they form three hydrogen bonds and pair up
So Adenine complements only thymine and guanine complements cytosine and there aren't any chances of guanine pairing up with thymine.
I think the enzyme photolyase is activated by light and can repair thymine dimers caused by UV radiation. Exposure to UV radiation is the main factor that causes skin cells to become cancer cells. These enzymes are involved in the repair of ultraviolet light-induced DNA damage when activated by light absorption.
