Which of the following reaction is associated with decarboxylation reactions during the Citric acid Cycle?(a) Isocitrate → α-Ketoglutarate(b)  α-Ketoglutarate →Succinyl CoA(c) Succinate →Fumarate(d) Pyruvate →Acetyl CoA

In Kreb's cycle or Citric acid cycle when Isocitrate is converted to α-Ketoglutarate and α-Ketoglutarate is converted to Succinyl CoA CO2 is released. When pyruvate is converted to acetyl CoA then also CO2 is released but it is a part of link reaction and not Kreb's cycle.