C(s) + CO2(g) ⇌ 2CO(g) If this system is at equilibrium, which change(s) will alter the value of Kp? — Equilibrium Chemistry Question

C(s) + CO₂(g) ⇌ 2CO(g)
If this system is at equilibrium, which change(s) will alter the value of Kp?
I. raising the temperature
II. adding solid C
III. decreasing the pressure