JEE Main Chemistry question

A quantity of PCl₅ was heated in a 10 litre vessel at 250°C to form PCl₅(g) ⇌ PCl₃(g) + Cl₂(g). At equilibrium, the vessel contains 0.1 mole of PCl₅, 0.20 mole of PCl₃ and 0.20 mole of Cl₂. The equilibrium constant is:

• (A)0.02
• (B)0.05
• (C)0.04Correct
• (D)0.025