Correct Option: D

Globulins contained in human blood plasma are primarily involved in defence mechanism of body. Globulin is one of the two types of serum proteins, the other being albumin. Globulins can be divided into three fractions based on their electrophoretic mobility. Most of the alpha and beta globulins are synthesized by the liver, whereas gamma globulins are produced by lymphocytes and plasma cells in lymphoid tissue.