Final answer:
Topoisomerase is an enzyme that reduces the torque that builds ahead of the replication fork by introducing small cuts in the DNA strands, unwinding them, and resealing the cuts.
Step-by-step explanation:
The enzyme described in the question is topoisomerase. Topoisomerase is responsible for reducing the torque or strain that builds up ahead of the replication fork during DNA replication.
It does this by introducing small cuts in the DNA strands, unwinding them, and then resealing the cuts. This process relieves the pressure that results from supercoiling and allows the replication fork to continue moving along the DNA strand smoothly.