Answer:
a. pyruvate is broken down into Co2 molecules
Step-by-step explanation:
Krebs cycle is also known as Citric Acid Cycle, in which pyruvate formed during the glycolytic is broken down into Carbon Dioxide (CO2) and Water (H2O).
Each pyruvate molecule is broken down into carbon atom which releases carbon dioxide.
Hence, the correct answer is "a. pyruvate is broken down into Co2 molecules".