Anaerobic respiration, the link reaction, and oxidative phosphorylation are essential stages in cellular respiration.

Which of the following statements about these processes is/are correct?

1. In anaerobic conditions in yeast, pyruvate is decarboxylated to ethanal before being reduced to ethanol to regenerate oxidized NAD.
2. The conversion of pyruvate to acetate in the link reaction is an oxidation reaction that is coupled to the reduction of NAD.
3. During oxidative phosphorylation, the energy released by the electron transport chain is used to actively pump protons from the intermembrane space into the mitochondrial matrix.

A. 1, 2 and 3 are correct B. only 1 and 2 are correct C. only 2 and 3 are correct D. only 1 is correct