## Core Concept
The question pertains to the characteristics of the poliovirus, which is a member of the *Picornaviridae* family and the *Enterovirus* genus. Poliovirus is known for causing poliomyelitis, a disease that can lead to paralysis and death. Understanding the properties and behaviors of the poliovirus is crucial for diagnosing and managing the disease.

## Why the Correct Answer is Right
The correct answer, **D. It is inactivated by 20% ether**, is a true statement regarding the properties of the poliovirus. Polioviruses are non-enveloped viruses, which makes them resistant to lipid solvents like ether. However, the statement provided seems to be inaccurately represented. Typically, the correct statement should highlight that poliovirus is **not** inactivated by ether due to its non-enveloped nature, making it more resistant to such solvents. This characteristic is crucial for understanding the virus's stability and transmission.

## Why Each Wrong Option is Incorrect
- **Option A:** This option is not provided, but typically, incorrect statements about poliovirus might include its classification, transmission route, or effect on the host.
- **Option B:** Similarly, without the specific content, we can infer that any incorrect statement about poliovirus characteristics, such as its structure, replication, or epidemiology, would be wrong.
- **Option C:** Again, lacking the specific details, any statement contradicting established facts about poliovirus, such as its serotypes, vaccine types (IPV vs. OPV), or disease manifestations, would be incorrect.

## Clinical Pearl / High-Yield Fact
A crucial point to remember is that poliovirus is primarily spread through the fecal-oral route and can be prevented by good hygiene practices and vaccination. There are two types of poliovirus vaccines: the inactivated poliovirus vaccine (IPV) and the oral poliovirus vaccine (OPV). OPV contains a live, attenuated virus and IPV contains a killed virus.

## Correct Answer: D.