The correct response regarding the products of the Krebs cycle (also known as the citric acid cycle or tricarboxylic acid cycle) after one molecule of glucose has gone through it is:
6 NADH, 2 ATP, 4 CO2, and 2 FADH2
This is because one glucose molecule is broken down into two pyruvate molecules, and each pyruvate enters the Krebs cycle, resulting in the production of the above-mentioned products for the total yield from one glucose molecule entering glycolysis and two pyruvates being processed in the Krebs cycle.