Question

what role does base pairing play in dna replication? it promotes the separation of the two strands of dna. it acts as a fail - safe, ensuring the correct base pairs are matched during replication. it helps in connecting the two strands of dna

Explanation:

To determine the role of base pairing in DNA replication, we analyze each option:

• The first option is incorrect because enzymes (like helicase) promote DNA strand separation, not base pairing.
• The second option is correct. Base pairing (A - T, G - C) ensures that during replication, the correct nucleotides are added to the new strand, acting as a mechanism to ensure fidelity (a "fail - safe" for accurate replication).
• The third option is incorrect. Base pairing holds the two DNA strands together in the double helix, but during replication, the strands are separated, and base pairing is about matching new nucleotides, not connecting the original two strands during replication.

Answer:

B. It acts as a fail - safe, ensuring the correct base pairs are matched during replication.