Asubstrate-level phosphorylation occurs in the citric acid cycle when a. atp is hydrolyzed to adp. b. nad+ is phosphorylated to nadh. c. gdp is phosphorylated to produce gtp d. pyruvate is oxidized

Substrate level phosphorylation occurred in kreb cycle inform of metabolic reaction that involve the transfer of phosphoryl group to GDP or ADP from another phosphorylated compound which result into formation of GTP or ATP. This process commonly occurs in the cytoplasm of cells during glycolysis and also in the mitochondria during krebs cycle.