Which of the following food items is produced by the fermenting activity of microbes?
A. ldli B. Dosa
C. Toddy D. Cheese

Options

A. A and C
B. C and D
C. A,B and C
D. A,B,C and D

Explanation

To determine which food items are produced by the fermenting activity of microbes, let's analyze each option step by step.

### Step 1: Analyze Idli
- **Idli** is a traditional South Indian dish made from fermented rice and lentil batter. The fermentation process involves the action of specific bacteria, primarily from the genera **Leuconostoc** and **Streptococcus**. The batter is typically allowed to ferment for about 3 to 12 hours before cooking.

### Step 2: Analyze Dosa
- **Dosa** is another South Indian dish that is closely related to idli. It is also made from a fermented batter of rice and lentils. The fermentation process is similar to that of idli, involving the same types of bacteria. Thus, dosa is also produced through the fermenting activity of microbes.

### Step 3: Analyze Toddy
- **Toddy** is a traditional alcoholic beverage made from the sap of palm trees. The fermentation occurs naturally as wild yeast and bacteria present in the environment act on the sap, converting sugars into alcohol. Therefore, toddy is also a product of microbial fermentation.

### Step 4: Analyze Cheese
- **Cheese** is a dairy product that is produced through the fermentation of milk. The process involves the action of specific bacteria and enzymes that curdle the milk, separating it into curds and whey. Thus, cheese is also produced by the fermenting activity of microbes.

### Conclusion
After analyzing all the options:
- Idli (A) is produced by fermentation.
- Dosa (B) is produced by fermentation.
- Toddy (C) is produced by fermentation.
- Cheese (D) is produced by fermentation.

Therefore, all options (A, B, C, and D) are correct.

### Final Answer
The correct option is: **A, B, C, D**.

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