Which of the Following Equilibria Would Not Be Affected by Pressure

Which of the following equilibria would not be affected by pressure change at constant temperature?

A) CO₂(g) + H₂(g) $\rightleftharpoons$ CO(g) + H₂O(g)
B) CO(g) + $\frac { 1 } { 2 }$ O₂(g) $\rightleftharpoons$ CO₂(g)
C) 2 Hg( $\ell$ ) + O₂(g) $\rightleftharpoons$ 2 HgO(s)
D) 2 H₂(g) + O₂(g) $\rightleftharpoons$ 2 H₂O( $\ell$ )
E) CaCO₃(s) $\rightleftharpoons$ CaO(s) + CO₂(g)