A hydrocarbon AC4H8 on reaction with HCI gives a compound BC4H9Cl which on reaction with 1 mole of NH3 gives a compound CC4H11 N. On reacting with NaNO2 and HCI followed by treatment with water, compound 'C yields an optically active alcohol, D. Ozonolysis of A gives 2 moles of acetaldehyde.The structure of compound C is