The Following Figure Shows the First Cycle in Polymerase Chain

The following figure shows the first cycle in polymerase chain reaction (PCR) . What is the role of the structure marked "P" in this figure?

A) The "P" represents the heat-tolerant DNA polymerase used in PCR to copy the gene of interest.
B) The "P" represents a sequence of DNA complementary to parts of the gene being amplified that allows DNA polymerase to attach to the gene.
C) The "P" indicates where on the DNA that DNA polymerase should terminate replication.
D) The "P" indicates the location of the promoter for the gene being amplified.