The link between glycolysis and the Krebs cycle is

Explanation

Acetyl-CoA is the correct option because it is the compound that forms the direct link between glycolysis and the Krebs cycle. During glycolysis, glucose is broken down into pyruvate, which is then converted into acetyl-CoA through the link reaction in the mitochondria. This acetyl-CoA then enters the Krebs cycle by combining with oxaloacetic acid to form citric acid, beginning the cycle. Succinic acid, citric acid, and oxaloacetic acid are all intermediates that occur within the Krebs cycle itself and do not serve as the connecting compound between glycolysis and the Krebs cycle. Therefore, only acetyl-CoA represents the true link between these two stages of respiration.