Which is the link reaction (gateway step) between glycolysis and citric acid cycle ?

Explanation

### Step-by-Step Solution:

1. **Understanding Glycolysis**: Glycolysis is the metabolic pathway that converts glucose into pyruvate, producing a small amount of ATP and NADH in the process.

2. **Identifying the Link Reaction**: The link reaction is the process that connects glycolysis to the citric acid cycle (Krebs cycle). This step is crucial as it prepares the products of glycolysis for entry into the citric acid cycle.

3. **Conversion of Pyruvate**: The product of glycolysis, pyruvate, undergoes a transformation during the link reaction. Pyruvate is converted into acetyl-CoA.

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