The answer is IgA.
The immunoglobulin can occur as a monomer or dimer. The dimeric form is called secretory-IgA because it is also secreted by glands that
produce saliva, tears, sweat, and in the lumen
of the gastrointestinal tract. It is the most secreted Immunoglobulin.
Answer: Incorrectly paired nucleotides that still remain following mismatch repair become permanent mutations after the next cell division.
Explanation: If they replicated than the entire thing would copy that and would be permanent.
D. would be the answer because they are all within the eukaryote kingdom