Rising of dough is due is

Options

A. a) multiplication of yeast
B. b) production of `CO_(2)`
C. c) emulsification
D. d) hydrolysis of wheat flour strach into sugars.

Answer

### Step-by-Step Solution:

1. **Understanding the Ingredients**: The dough is made up of various ingredients, including flour, water, sugar, and yeast. Yeast is a crucial component in the dough-making process.

2. **Role of Yeast**: Yeast is a type of fungus that ferments sugars present in the dough. When yeast is added to the dough, it begins to consume the sugars.

3. **Fermentation Process**: During fermentation, yeast breaks down the sugars to produce energy. This process is similar to how humans metabolize food for energy.

4. **Production of Carbon Dioxide**: As a byproduct of fermentation, yeast produces carbon dioxide (CO2) gas. This gas is what causes the dough to rise.

5. **Conclusion**: The rising of the dough is primarily due to the production of carbon dioxide by the yeast during the fermentation process.

6. **Evaluating Options**:
- **Option A**: Multiplication of yeast - Incorrect, as yeast multiplication does not produce CO2.
- **Option B**: Production of CO2 - Correct, as this is the reason for the rising of dough.
- **Option C**: Emulsification - Incorrect, as emulsification refers to mixing immiscible substances and is not related to dough rising.
- **Option D**: Hydrolysis of wheat flour and starch into sugars - Incorrect, as this does not directly cause the dough to rise.

### Final Answer:
The rising of dough is due to the production of carbon dioxide (CO2) by yeast during fermentation.

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