In manufacture of bread, it becomes porous due to release of `CO_(2)` by the action of

Options

A. Yeast
B. Bacteria
C. Virus
D. Protozoans

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the process that makes bread porous due to the release of carbon dioxide (CO₂).

2. **Identifying the Microorganism**: The options provided are yeast, bacteria, virus, and proposites. Among these, yeast is known for its role in bread making.

3. **Fermentation Process**: Yeast carries out fermentation, which is a type of anaerobic respiration. This means that yeast can convert sugars into alcohol and carbon dioxide in the absence of oxygen.

4. **Alcoholic Fermentation**: During the fermentation process, yeast converts glucose (sugar) into ethanol (alcohol) and CO₂. This process is specifically called alcoholic fermentation.

5. **Role of CO₂ in Bread Making**: The CO₂ produced during fermentation gets trapped in the dough. As the dough rises, the gas expands, creating bubbles that make the bread porous and light.

6. **Baking Process**: When the bread is baked, the heat causes the alcohol to evaporate, and the CO₂ gas expands further, contributing to the bread's light and airy texture.

7. **Conclusion**: Therefore, the correct answer to the question is that bread becomes porous due to the release of CO₂ by the action of yeast.

**Final Answer**: Yeast.

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