Which of the following accurately describes the structure of dna? a. a always pairs with c, and g always pairs with t. b. dna consists of four bases: a, g, c, and u. c. dna is made up of nucleotides, containing a 3-carbon sugar, a phosphate group, and base. d. dna is in the form of antiparallel strands twisted as a double helix.

Among the choices given, the one that accurately describes the structure of DNA is D. DNA is in the form of anti-parallel strands twisted as a double helix. Moreover, DNA is primarily made up of nucleotides which consists of a nitrogenous base, at least one phosphate group, and a five-carbon sugar. It should also be noted that purine adenine (A) only pairs with pyrimidine thymine (T) and the purine guanine (G) with pyrimidine cytosine (C).