Another thermophile, Thermus aquaticus, was isolated from a hot spring in Yellowstone National Park. It is the source of the enzyme Taq polymerase, which is used in the molecular technique called polymerase chain reaction (PCR). PCR is used to amplify sequences of DNA. What extremophile characteristic of this enzyme makes it an essential component in a PCR reaction?a. Taq polymerase is stable under acidic or alkaline conditions.
b. Taq polymerase is stable under extremely cold temperatures.
c. Taq polymerase is heat-stable and can withstand high temperatures.
d. Taq polymerase is stable in solutions that are extremely high in salt.

c. Taq polymerase is heat-stable and can withstand high temperatures.

Explanation:

The process of PCR amplifies a small amount of DNA into multiple copies. For the purpose, the sample DNA fragments are denatured at higher temperature conditions (around 95 degrees Celsius). This separates the two strands of the sample DNA which in turn serve as a template. Taq polymerase from a thermophile can withstand the extremes of the temperature conditions required for denaturation of sample DNA. Unlike the DNA polymerases from other organisms such as humans, Taq polymerase is not denatured at higher temperatures.

Therefore, Taq polymerase can be used as an enzyme of primer elongation to amplify the DNA by PCR.

substitution is the answer in this case