## **Core Concept**
The question pertains to the disinfection of choleric stools using bleaching powder, which is a method of controlling the spread of cholera, a diarrheal disease caused by *Vibrio cholerae*. The process involves using a disinfectant to kill the bacteria in the stool.

## **Why the Correct Answer is Right**
The correct answer, , implies that 1 part of bleaching powder is used for 10 parts of choleric stools. This ratio is significant because bleaching powder (calcium hypochlorite) is a strong disinfectant. When it comes into contact with organic matter, it releases hypochlorous acid, which is toxic to *Vibrio cholerae*. The effectiveness of bleaching powder in killing pathogens depends on the concentration of available chlorine and the contact time.

## **Why Each Wrong Option is Incorrect**
- **Option A:** . This option suggests a much higher concentration of bleaching powder than necessary, which could be unnecessarily harsh and potentially hazardous but does not directly relate to the standard recommendations for stool disinfection.
- **Option B:** . This ratio seems less effective compared to the correct answer, potentially leaving *Vibrio cholerae* viable.
- **Option D:** . This option implies a much lower concentration of bleaching powder, which might not effectively disinfect the stools.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that for effective disinfection of cholera stools, a 1:10 ratio of bleaching powder to stool is often recommended. This practice is crucial in areas where cholera outbreaks occur, as it helps prevent the spread of the disease.

## **Correct Answer:** .