One Mole of Hydrogen, One Mole of Nitrogen and One

One mole of hydrogen, one mole of nitrogen and one mole of oxygen are held in a 22.4 × 10³ cm³ enclosed vessel at 20°C. The pressure in the vessel, in N/m², is

A) 109.
B) 304.
C) 326.
D) 1.09 × 10⁵.
E) 3.26 × 10⁵.