6-NADH can yield:

Explanation

An NADH molecule on oxidation theoretically releases sufficient energy to make 3 ATP molecules. Therefore, 6 molecules of NADH can yield:6 NADH → 6 3 = 18 molecules of ATPThe actual yield of ATP per molecule of NADH is however less. It's 2.5 molecules of ATP/NADH. Therefore, the actual yield of ATP when 6 NADH molecules undergo oxidation is:6 NADH → 6 2.5 = 15 molecules of ATPSince 15 molecules of ATP is not given as an option, the theoretical yield of ATP i.e. 18 molecules (Option C) is the answer.