Which of the following cells is responsible for the production of antibodies in response to infection or vaccination?

Explanation: B cells are a type of lymphocyte that plays a central role in the adaptive immune response. When activated by the presence of specific antigens, B cells differentiate into plasma cells, which are responsible for producing large quantities of antibodies that can target and neutralize the invading pathogen.

Incorrect choices:

a. T cells are another type of lymphocyte that is involved in cell-mediated immunity, where they directly attack infected or abnormal cells. They do not produce antibodies.

b. Natural killer cells are part of the innate immune system and are responsible for killing infected or cancerous cells. They are not involved in antibody production.

d. Macrophages are phagocytic cells that engulf and destroy pathogens and debris in the body. While they play a crucial role in immune responses, they do not produce antibodies.

Explanation: Live attenuated vaccines use a weakened form of the pathogen that is still capable of replicating but does not cause severe illness in healthy individuals. This type of vaccine can provide long-lasting immunity with a single dose.

Incorrect choices:

a. Inactivated vaccines use killed pathogens, not weakened forms.

b. Subunit vaccines use only specific parts of the pathogen, not weakened forms.

d. Toxoid vaccines use inactivated toxins produced by the pathogen, not weakened forms of the pathogen itself.