Consider the following reaction (assume an ideal gas mixture). 2NOBr(g) -> 2NO(g) + Br2(g) A 3.0-L vessel was initially filled with pure NOBr, at a pressure of 3.7 atm, at 3290 K. After equilibrium was reached, the volume was increased to 2.0 L, while the temperature was kept at 300 K. This will result in:

A. an increase in Kp.
B. a decrease in Kp.
C. a shift in the equilibrium position to the right.
D. a shift in the equilibrium position to the left. E) none of these