Answer:
C. During pyruvate processing
Step-by-step explanation:
Acetyl CoA is the initiator of the citric acid cycle which is formed by the end product of the glycolysis that is pyruvic acid. It is the link between glycolysis and the citric acid cycle.
Each pyruvate is processed in this process to release one molecule of CO₂, and the remaining two carbon molecule is formed Acetyl CoA.