In class switching in the secondary antibody response, the most common antibody switch is from

I believe that the most common antibody switch is from IgM to IgG.
Class switching occurs by a mechanism called the class switch recombination binding. It is a biological mechanism that allows the class of antibody produced by an activated B cell to change during a  process known as isotype or class switching. The mechanism changes a B cell's production of antibodies from one form  to another, such as from the isotype IgM to the isotype IgG.

D. china is one of the most active places, which could quite possibly mean more agriculture will happen.. and more war machi-    best of luck comrade.

The correct answer is:       [c]:   "organisms that are sensitive to changes in temperature would die. "