Answer:
The correct answer is C) a virus.
Step-by-step explanation:
Polymerase chain reaction (PCR) is a laboratory technique used to amplify specific DNA sequences. The PCR process involves several key components, including a thermocycler, DNA primers, and a DNA polymerase. However, a virus is not typically used as part of the PCR process.
The thermocycler is used to control the temperature of the reaction mixture, which allows for the denaturation (separation) of double-stranded DNA, annealing of the DNA primers to the single-stranded DNA template, and extension of the primers by the DNA polymerase.
The DNA primers are short pieces of DNA that are complementary to the target DNA sequence and provide a starting point for DNA polymerase to extend and copy the DNA sequence.
The DNA polymerase is the enzyme responsible for adding nucleotides to the growing DNA chain during PCR.
In summary, a virus is not used as part of the process of polymerase chain reaction, while a thermocycler, DNA primers, and a DNA polymerase are all essential components.