Yeast secrets an enzyme which is responsible for fermentation. This enzyme is :

Options

A. Invertage
B. Zymase
C. Dehydrogenes
D. Aldolase

Explanation

To answer the question regarding the enzyme secreted by yeast that is responsible for fermentation, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Context**: The question is about yeast and its role in fermentation. Yeast is a type of fungus that plays a crucial role in converting sugars into alcohol and carbon dioxide through fermentation.

2. **List the Options**: The options provided are:
- Invertase
- Mes
- Dehydrogenase
- Aldolase

3. **Understand Fermentation**: Fermentation is a metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen. Yeast is commonly used in the fermentation of sugars to produce ethanol (alcohol) and carbon dioxide.

4. **Identify the Correct Enzyme**: The enzyme that yeast secretes to facilitate fermentation is known as "thymase." This enzyme helps in the conversion of sugars into ethanol and carbon dioxide.

5. **Conclusion**: Based on the information and understanding of yeast and fermentation, the correct answer to the question is "thymase."

### Final Answer:
The enzyme secreted by yeast that is responsible for fermentation is **thymase**.

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