[A]: Glycolysis yields 2ATP & 2NADH only.
[R]: Glycolysis is an anaerobic process & can't oxidise substrate fully.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

To analyze the assertion and reason provided in the question, we will break it down step by step.

### Step-by-Step Solution:

1. **Understanding Glycolysis**:
- Glycolysis is the metabolic pathway that converts glucose into pyruvate, producing energy in the form of ATP and NADH.
- It occurs in the cytoplasm of the cell and does not require oxygen, making it an anaerobic process.

2. **Analyzing the Assertion**:
- The assertion states: "Glycolysis yields 2 ATP & 2 NADH only."
- This is correct because, during glycolysis, a net gain of 2 ATP molecules and 2 NADH molecules is produced from one molecule of glucose.

3. **Analyzing the Reason**:
- The reason states: "Glycolysis is an anaerobic process & can't oxidize substrate fully."
- This is also correct. Glycolysis does not require oxygen, and it only partially oxidizes glucose into pyruvate, not fully breaking it down into carbon dioxide and water.

4. **Connecting Assertion and Reason**:
- The reason explains why the yield of ATP and NADH is low in glycolysis. Since it does not fully oxidize glucose, the energy yield is limited compared to aerobic respiration, which occurs in the mitochondria and produces more ATP.

5. **Conclusion**:
- Both the assertion and reason are true, and the reason correctly explains the assertion. Therefore, the correct answer is that both statements are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, and the reason is the correct explanation of the assertion.

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