Two Masses Are Connected by a String Which Passes Over

Two masses are connected by a string which passes over a pulley with negligible mass and friction.One mass hangs vertically and one mass slides on a 30.0 degrees frictionless incline.The vertically hanging mass is 4.0 kg and the mass on the incline is 6.00 kg.The acceleration of the 4.00 kg mass is

A) 0.980 m/s².
B) 3.92 m/s².
C) 5.75 m/s².
D) 6.86 m/s².
E) 7.84 m/s².