What is the best explanation for Chargaff's rules?
A. there is always double amount of pyrimidine than purine bases in the double helix of DNA
B. there is pairing between G and T and A and C in the double helix of DNA
C. there is pairing between G and C and A and T in the double helix of DNA
D. there is pairing between G and C and A and U in the RNA
E. C and D are correct