How many types of antibodies are produced in our body?

Assertion $(A)$: The human body is exposed to a large number of infectious agents daily,yet only a few result in disease. Reason $(R)$: The human body possesses an immune system. Which option is correct for Assertion $(A)$ and Reason $(R)$?

Which of the following is a non-specific type of defense that is present at the time of birth?

What does the term 'memory' of the immune system mean?

The principle of Vaccination and Immunization is based on which property of the immune system?

Which of the following provides passive immunity?