What are these markers called?

The surface of most vertebrate cells possesses self-markers called major __________.?

• The surface of most vertebrate cells possesses self-markers called major __________. A) Histocompatibility complex proteins B) T-cell receptors C) Antigens D) Immunoglobulins E) Toll-like receptors

• Answer:

  It's A, and are often referred to as HMC proteins. Without them, the body would attack itself.