At 320 K and 16 Atm Pressure,the Molar Volume of Ammonia,NH₃,is

At 320 K and 16 atm pressure,the molar volume of ammonia,NH₃,is about 10% less than the molar volume of an ideal gas.The best explanation for actual volume being this much smaller than ideal volume is that

A) the intermolecular forces of attraction become significant at this temperature and this pressure.
B) the critical temperature and pressure of NH₃ (405 K and 112 atm) are too close to the actual temperature and pressure of the NH₃ above.
C) at this high temperature,a significant amount of NH₃ decomposes to N₂ and H₂.
D) ammonia is a real gas and not an ideal gas.
E) the volume occupied by the NH₃ molecules themselves is significant at this high concentration.