Consider the following reaction:

2 NO(g) + O2(g) ---> 2 NO2(g) + energy
if the number of moles of oxygen is increased to two moles, the

a. reaction speeds up
b. reaction slows down
c. temperature increases
d. temperature decreases

I'm not really sure what the answer to this is...I'm really stuck between A and C.

I would go with Le Chatelier's Principle. Increasing (O2) will shift the equilibrium to the right.