## Core Concept
Bleaching powder, chemically known as calcium hypochlorite (Ca(ClO)_2), is a disinfectant commonly used for water treatment and as a bleaching agent. Its effectiveness is primarily due to its ability to release hypochlorous acid (HOCl), a potent disinfectant.

## Why the Correct Answer is Right
The correct answer is related to the properties and uses of bleaching powder. However, without the specific details of options A, B, C, and D, we can infer that the right answer pertains to a characteristic or application that does not align with the known properties or uses of bleaching powder.

## Why Each Wrong Option is Incorrect
- **Option A:** Without specifics, we can't directly address why A is incorrect, but we can infer that if A states a true property or use of bleaching powder, it would be a correct statement regarding its composition, mechanism of action, or application.
- **Option B:** Similarly, if B is incorrect, it might claim a property or use not attributed to bleaching powder, such as an incorrect chemical composition or an ineffective application.
- **Option C:** This option would be incorrect based on similar reasoning; if it suggests something bleaching powder does or is that is not accurate, it would be a wrong statement.
- **Option D:** The correct answer being "D" implies that D is the statement that does not hold true for bleaching powder.

## Clinical Pearl / High-Yield Fact
A key point to remember is that bleaching powder's effectiveness as a disinfectant is significantly reduced in the presence of organic matter, and it should be used in appropriate concentrations to avoid toxicity and ensure efficacy.

## Correct Answer Line
**Correct Answer: D.**