All of the Following Are True About Biological Response Modifiers

All of the following are true about biological response modifiers except:

A) They alter the body's defense system to enhance removal of the foreign cancer cell.
B) Some are immunostimulants, and, when given with other antineoplastic agents, help limit severe myelosuppression.
C) They are used to prevent transplant rejections.
D) They are more toxic than are most classes of antineoplastics.