## Core Concept
The National Polio Eradication Programme aims to eradicate poliomyelitis through vaccination and surveillance. A key component of this surveillance is the detection and investigation of Acute Flaccid Paralysis (AFP) cases, as polio can cause AFP. The programme uses specific criteria to confirm whether an AFP case is due to poliovirus.

## Why the Correct Answer is Right
To confirm a case of AFP as polio under the National Polio Eradication Programme, specific conditions must be met, typically involving the presence of residual weakness after 60 days, the absence of other causes of AFP, and laboratory confirmation of poliovirus infection. The correct answer will relate to the exception among the given options regarding these conditions.

## Why Each Wrong Option is Incorrect
- **Option A:** This option would typically describe a scenario where a case of AFP is confirmed as polio, such as a case with laboratory-confirmed poliovirus infection.
- **Option B:** Similarly, this might outline another condition under which AFP is confirmed as polio, like the presence of residual weakness and no other cause identified.
- **Option D:** This could represent another criterion, such as a case that meets the World Health Organization's (WHO) case definition for polio.

## Clinical Pearl / High-Yield Fact
A crucial point to remember is that for AFP surveillance, a case is considered confirmed as polio if there's residual weakness after 60 days and laboratory confirmation of poliovirus, or if other causes of AFP are ruled out and there's an epidemiological link to a confirmed polio case.

## Correct Answer: D.