To decolorize green leaves usually ............. is used and the mixture is heated.

Options

A. Water
B. Oil
C. soap solution
D. none

Explanation

To answer the question about what is used to decolorize green leaves, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Purpose of Decolorization**:
- The purpose of decolorizing green leaves is to remove the green pigment, chlorophyll, which is essential for certain experiments, such as testing for starch.

2. **Identifying the Pigment**:
- Green leaves contain chlorophyll, which gives them their color. To perform experiments like staining or testing for starch, it is necessary to remove this green color.

3. **Choosing the Right Substance**:
- The options provided are water, oil, soap solution, and none. We need to determine which of these is effective for decolorization.

4. **Understanding the Decolorization Process**:
- The process of decolorization typically involves boiling the leaves in a suitable solvent. In this case, alcohol is commonly used because it effectively removes chlorophyll.

5. **Evaluating the Options**:
- Water: Not effective for decolorization.
- Oil: Not effective for decolorization.
- Soap solution: Not effective for decolorization.
- None: This option implies that none of the above substances are correct, which is true since alcohol is the correct choice.

6. **Conclusion**:
- Since alcohol is not listed as an option, the correct answer to the question is "none."

### Final Answer:
To decolorize green leaves, usually **none** is used, as alcohol is the correct substance for this process.

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