Which of the following cells are associated with the immune system of the body?

The defence mechanism of the body against different diseases is known as:

Which of the following provides passive immunity?
$i$. Colostrum
$ii$. Antibodies against rabies pathogens
$iii$. After recovery from measles
$iv$. Polio vaccine

Which of the following is a characteristic feature of acquired immunity?

Humans have an acquired immune system that produces antibodies to neutralize pathogens. Still,the innate immune system is present at the time of birth because it

Given below are two statements. Select the most appropriate answer from the given options.
Statement-$I$: $T$-lymphocytes have $4$ subtypes as helper,killer,memory,and suppressor $T$-cells.
Statement-$II$: $B$-lymphocytes mature in the thymus and are responsible for cell-mediated immunity.