Question

Assertion (A): A child who has had an acute attack of poliomyelitis should be administered oral polio vaccine.

Reason (R): There is no cross-immunity between the different types of polio viruses.

• A. Both A and R are true and R is the correct explanation of A
• B. Both A and R are true but R is NOT the correct explanation of A
• C. A is true but R is false
• D. A is false but R is true

Hint:

Recall that OPV covers three separate poliovirus serotypes.

Answer 1

The Correct Option is B

Step 1: Check the assertion.
A child who had paralytic polio was infected by only one of the three poliovirus types. Giving OPV afterward is still recommended so the child builds immunity to the other two types. This makes the assertion true.

Step 2: Check the reason.
The reason says there is no cross-immunity between the different polio virus types. This is a correct, well known virology fact by itself.

Step 3: See if the reason truly explains the assertion.
Continuing the vaccine schedule after an attack is a general immunization policy, not something derived only from the cross-immunity fact. The two statements stand independently true, but the reason is not framed as the direct cause the assertion relies on.

Step 4: Conclude.
Both statements are true, but the reason does not directly explain the assertion. The answer is that both A and R are true, but R is not the correct explanation of A.