Which of the following is used as a substrate for the production of `CH_3CH_2OH` ?

Options

A. Maize
B. Malted cereals
C. Lactose
D. None of the above

Answer

To solve the question "Which of the following is used as a substrate for the production of `CH_3CH_2OH` (ethanol)?", we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks for a substrate that is used in the production of ethanol (chemical formula: `CH_3CH_2OH`).

2. **Analyzing the Options**:
- **Option 1: Barley**:
- Barley is often used in the fermentation process to produce ethanol, particularly in brewing beer. It is malted to convert starches into sugars, which can then be fermented.
- **Option 2: Malted Cereals**:
- Malted cereals are grains that have been soaked, germinated, and dried. They are rich in sugars and are commonly used in the fermentation process to produce ethanol. This is a correct substrate for ethanol production.
- **Option 3: Lactose**:
- Lactose is a sugar found in milk. While it can be fermented, it does not directly lead to ethanol production in the same way that glucose or malted cereals do. Therefore, this option is incorrect.
- **Option 4: None of the Above**:
- Since we have identified that malted cereals are a substrate for ethanol production, this option is also incorrect.

3. **Conclusion**:
- The correct answer is **Option 2: Malted Cereals**, as they are used as a substrate for the production of ethanol.

### Final Answer:
**Option 2: Malted Cereals**