Chapter 15, Problem 14RA

Which of these statements about class-2 MHC molecules is false?

$\begin{array}{l}\text{a}\text{. They are found on the surface of B lymphocytes}\text{.}\hfill \\ \text{b}\text{. They are found on the surface of macrophages}\text{.}\hfill \\ \text{c}\text{. They are required for B cell activation by a foreign antigen}\text{.}\hfill \\ \text{d}\text{. They are needed for interaction of helper and cytotoxic T cells}\text{.}\hfill \\ \text{e}\text{. They are presented together with foreign antigens by macrophages}\text{.}\hfill \end{array}$