A 40-year-old chronic alcoholic presented to the OPD with complaints of B/L distal lower limb numbness and paresthesias along with weakness and dizziness. He has a history of stroke in the past. On examination, Characteristic skin lesions were observed Impaired vibration and proprioception Preserved pain and temperature Sensory ataxia Lab findings revealed a low EAST-AC value. Which of the following reactions uses the above deficient vitamin as coenzyme:-