Answer:
the answer is D.
Explanation:
The heritable variation is defined as the variance of the breeding values among individuals.
I believe the correct answer is homeostasis.
Adenine, Thymine, Cytosine and Guanine.
<u>Explanation</u>
In double helix, the nitrogenous bases of opposite nucleotides form pairs through hydrogen bonds. The nitrogenous base adenine of one nucleotide forms pair with thymine of opposite nucleotide, while cytosine forms pair with guanine.