Which describes the correct pairing of dna bases?

a. t with a, and c with g
b. t with c, and a with g
c. t with t, and c with c
d. t with g, and a with c

The correct answer would be A.T with A, and C with G

It can be explained with the help of complementary base pairing.

In DNA,  thymine (T) always forms a base pair with adenine (A) and cytosine (C) always base pairs with guanine (G) .

There are two hydrogen bonds present in between A and T and three hydrogen bonds in between G and C.

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."