OIt summarized the process of evolution.
3 is the answer.
Binary fission is a type of asexual reproduction and is the most common method of reproduction in prokaryotes. It may occur in some unicellular (single- celled) eukaryotes..
Eukaryotes use sexual recombination during reproduction to create or generate genetic variation and thus the resulting offspring will have a mixture of the parents' genetic characteristics.
Prokaryotes on the other hand will simply produce clones of themeslves through binary fisson. After the process of replicating its own genetic material, the prokaryote simply divides into two daughter cells that are almost identical in size and that concludes the process.
The right answer is D (less responsive to antigens)
It is proven that, after puberty, thymus activity (an organ that is included in the lymphatic system, producing T cells that pick up antigens) decreases and that in adult and aged people the thymus has no role. Work done in humans indicate that in fact the cellularity begins to decline from birth in favor of lymphocyte perivascular spaces and connective and adipose tissue, which leads to a decrease in the capture of antigens.