Question

a denaturing
b annealing
c extension
d none of the above
involves cooling the single strands of dna to allow the
primers to bind to the dna sequence.

Explanation:

PCR (Polymerase Chain Reaction) has three main steps. Denaturing involves heating DNA to separate strands. Annealing is cooling to allow primers to bind. Extension is DNA synthesis. The question describes annealing.

Answer:

B. Annealing