Which is true in base pair concentration

in an analysis of the nucleotide composition of double stranded dna to see which bases are equivalent in concentration, which is true?

A. A+C=G+T
B. A=C
C. A=G and C=T
D.both B and C are true

A binds to T
C binds to G

Therefore, A=T and C=G

So the answer is A, because A and T are equal, and C and G are equal, so when you add them up, you get the same sum.