Before a cell divides, it must duplicate its DNA. Which of the following best describes DNA replication? A. The two strands of a DNA molecule separate, and an exact copy of each strand is synthesized. B. The two strands of a DNA molecule separate, and a complementary strand is synthesized from each original strand. C. The two strands of a DNA molecule unwind, and an exact copy of one strand is synthesized. D. The two strands of a DNA molecule unwind, and a complementary strand is synthesized from one of the original strands.