Select the correct statement with respect to diseases and immunisation
A. Injection of snake antivenom against snake bite is an example of active immunisation.
B. If due to some reason B-and T-lymphocytes are damaged, the body will not produce antibodies against a pathogen.
C. Injection of dead/inactivated pathogens causes passive immunity
D. Certain protozoans have been used to mass produces hepatitis B vaccine
