Answer:
Option B, Cellular clock theory
Explanation:
The Cellular Clock Theory of Aging states that the older the cells get , the more they become incapable of reproducing or replicating. The telomeres (tip of the chromosomes) are DNA sequences which cap the chromosomes get smaller in size with time and eventually they hinder the cell division. As per a normal standard rate, a telomere replicates 70 to 80 times in its life span and then it stops replicating.
Hence, option B is correct
I think its D I'm not quite sure but with RNA the A changes to a U.
Homozygous - having two identical alleles on both chromosomes.
