Answer: B the ends of linear chromosomes.
Explanation:
Based on structure, telomeres are located at the end of chromosomes; they are protective caps that bind the genes at the end of the chromosomes in order to prevent it from interchromosomal fusion (clumping) and degradation (broken down). Simply, they serve the same role as plastic caps to the tip of shoe laces; preventing it from unraveling.
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Generally, telomeres becomes short in length with time. At this stage they become weaken, and breaks down. The affected the cells basic replication activites, and therefore the functions. These non-functioning cells accumulated in body organs, and made them to degenerate .This reduced longevity, leading to death of cells. However the shortening of the length is an advantage to prevent the spread of cancer in cells because I naturally stops the uncontrivable growth of cells
Therefore the longer the length of telomeres at the genome end of chromosomes, the higher the rate of replication of the concerned cells, and hence the increase in the age of the cell
