Which of the following statements is false? a. class 1 mhc molecules are built into the plasma membranes of all body cells. b. class ii mhc molecules appear only on the surface of antigen-presenting cells and t cells that have been activated by exposure to antigens. c. mhc proteins are the cell's identity markers. d. it is common for unrelated individuals to have the same mhc molecules.

The correct answer is option B.

Explanation:

MHC or The major histocompatibility complex is a series of genes that have information and rise to cell surface proteins required for the adaptive immune system to recognize the pathogen or the foreign molecules, There are three classes of MHC - MHC1, MHC2, and MHC3.

MHC class II generally present only on antigen-presenting cells such as single nuclear phagocytes, dendritic cells, thymic and B cells.

Thus, the correct answer is option B.