Select the Statement That Best Describes the Function of Heating

Select the statement that best describes the function of heating and cooling in PCR.

A) Heating facilitates strand denaturation,and cooling facilitates primer attachment.
B) Heating facilitates primer attachment,and cooling facilitates strand elongation.
C) Heating facilitates strand elongation,and cooling facilitates strand denaturation.
D) Heating facilitates strand denaturation,and cooling facilitates strand elongation.
E) Heating facilitates strand elongation,and cooling facilitates primer attachment.