The Answer is d.
Hope this helps:) Have yourself a great day:)
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.
A pathogen that has nutrients absorbed from its environment is called fungus. Fungus is a eukaryotic microorganism that is a heterotroph and acquire its food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment
