The correct option for the value of vapour pressure of a solution at \( 45^{\circ} C \) with benzene to octane in molar ratio \( 3: 2 \) is : [At \( 45^{\circ} C \) vapour pressure of benzene is \( 280\, mm\, Hg \) and that of octane is \( 420\, mm \,Hg \) . Assume Ideal gas]

(A) 160 mm of Hg
(B) 168 mm of Hg
(C) 336 mm of Hg
(D) 350 mm of Hg