JEE Main Chemistry question

The equilibrium constant for the reaction 3C₂H₂ ⇌ C₆H₆ is 4.0 at T K. If the equilibrium concentration of C₂H₂ is 0.5 mol/litre, the concentration of C₆H₆ is:

• (A)0.5 MCorrect
• (B)1.5 M
• (C)5×10⁻² M
• (D)0.25 M