Select the correct statement with respect to diseases and immunisation

Options

A. If due to some reason B and T lymphocytes are damaged, then the body will not produce antibodies against a pathogen.
B. Injection of dead or inactivated pathogens causes passive immunity.
C. Certain protozoans have been used in mass production of hepatitis B vaccine.
D. Injection of snake antivenom against snake bite is an example of active immunisation.

Answer

A