Which of Thfollowing Statements Is True

Which of thfollowing statements is true?

A) The hydrogen bonding of guanine to cytosine is an example of complementary base pairing.
B) Adenine always pairs up with guanine in DNA, and cytosine always teams up with thymine.
C) Each of the four nucleotides in a DNA molecule has the same nitrogen-containing base.
D) When adenine base pairs with thymine, they are linked with three hydrogen bonds.
E) In the DNA of all species, the amount of A+C never equals the amount of T+G.