Assertion: Fermentation accounts for only a partial breakdown of glucose whereas in aerobic respiration it is completely degraded to `CO_(2)" and "H_(2)0`
Reason: NADH is oxidised to `NAD^(+)` rather slowly in aerobic respiration, however the reaction is very vigorous in case of fermentation.

Options

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

Explanation

To analyze the assertion and reason provided in the question, we will follow these steps:

### Step 1: Understand the Assertion
The assertion states that "Fermentation accounts for only a partial breakdown of glucose whereas in aerobic respiration it is completely degraded to CO₂ and H₂O."

- **Explanation**: This is true. In aerobic respiration, glucose (C₆H₁₂O₆) is fully oxidized in the presence of oxygen to produce carbon dioxide (CO₂), water (H₂O), and energy (ATP). In contrast, fermentation is an anaerobic process (occurs without oxygen) that results in the partial breakdown of glucose, producing byproducts such as ethanol or lactic acid, along with a small amount of ATP.

### Step 2: Understand the Reason
The reason states that "NADH is oxidized to NAD⁺ very slowly in aerobic respiration, however the reaction is very vigorous in case of fermentation."

- **Explanation**: This statement is incorrect. In aerobic respiration, the oxidation of NADH to NAD⁺ occurs efficiently and is coupled with the electron transport chain, leading to a significant production of ATP. In fermentation, while NADH is also oxidized to NAD⁺, the process is not necessarily "vigorous" but rather occurs to regenerate NAD⁺ to allow glycolysis to continue in the absence of oxygen. Thus, the reason does not accurately describe the processes involved.

### Step 3: Conclusion
- The assertion is true, while the reason is false. Therefore, the reason does not provide a correct explanation for the assertion.

### Final Answer
The correct answer is that the assertion is true, but the reason is false.

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