Choose the word which is different from the rest.

The answer is E. Pepsinogen.

Lymphocytes, plasma, fibrinogen, and hemoglobin are all components of blood. Lymphocytes are a type of white blood cell that helps the body fight infection. Plasma is the liquid part of blood that carries nutrients, hormones, and other substances to the body’s cells. Fibrinogen is a protein that helps blood clot. Hemoglobin is a protein in red blood cells that carries oxygen to the body’s tissues. Pepsinogen is a protein that is converted to pepsin in the stomach, which helps break down proteins.

Pepsinogen is the only option that is not a component of blood.