To solve this problem, we need to analyze each statement about the Krebs' cycle and identify the incorrect one. Let's evaluate each option:$\newline \bullet$Option 1: There is one point in the cycle where FAD+ is reduced to FADH2.$\newline$ - This statement is correct. In the Krebs' cycle, FAD+ is reduced to FADH2 during the conversion of succinate to fumarate.$\newline \bullet$Option 2: During conversion of succinyl CoA to succinic acid, a molecule of GTP is synthesized.$\newline$ - This statement is correct. The conversion of succinyl CoA to succinic acid is coupled with the synthesis of GTP (or ATP in some organisms).$\newline \bullet$Option 3: The cycle starts with condensation of acetyl CoA with pyruvic acid to yield citric acid.$\newline$ - This statement is incorrect. The Krebs' cycle starts with the condensation of acetyl CoA with oxaloacetic acid to form citric acid, not pyruvic acid.$\newline \bullet$Option 4: There are three points in the cycle where NAD+ is reduced to NADH + H+.$\newline$ - This statement is correct. NAD+ is reduced to NADH + H+ at three points in the Krebs' cycle: during the conversion of isocitrate to alpha-ketoglutarate, alpha-ketoglutarate to succinyl CoA, and malate to oxaloacetate.$\newline$Therefore, the incorrect statement is Option 3, which states that the cycle starts with the condensation of acetyl CoA with pyruvic acid.