Which of the following best describes the complete sequence of steps occurring during every cycle of PCR? 1)The primers hybridize to the target DNA. 2)The mixture is heated to a high temperature to denature the double-stranded target DNA. 3)Fresh DNA polymerase is added. 4)DNA polymerase extends the primers to make a copy of the target DNA.
A) 2, 1, 4 B) 1, 3, 2, 4 C) 3, 4, 1, 2 D) 3, 4, 2 E) 2, 3, 4