The proteins that help defend the body against bacteria, toxins, and allergens are called antibodies. The antibody<span> (Ab) protein is also known as an immunoglobulin (Ig).
</span>These<span> large Y-shaped proteins are</span><span> produced by the immune system in order to prevent the body in response to the presence of a foreign substance. The foreign substance is called antigen.
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I dont think i'm answering your question, but the sun turns into a red giant, and the more it gets bigger it gets, the more closer it is to the planets. Then eats up the the planets later on, and explodes. Dont know if im correct tho sorry
I do believe that it is C. crossing over :) I hope that is correct, it seems like the only plausible answer.