Which of the Following Is the Correct Sequence of the Polymerase

Which of the following is the correct sequence of the polymerase chain reaction?

A) heat to 70°C (to separate DNA) , then cool to 50°C (to bind primers and enzymes) , then reheat to 90°C (to synthesize DNA)
B) heat to 90°C (to bind primers and enzymes) , then cool to 50°C (to separate DNA) , then reheat to 70°C (to synthesize DNA)
C) heat to 70°C (to bind primers and enzymes) , then cool to 50°C (to synthesize DNA) , then reheat to 90°C (to separate DNA)
D) heat to 90°C (to separate DNA) , then cool to 50°C (to bind primers and enzymes) , then reheat to 70°C (to synthesize DNA)