Solve : $ y dx +x dy +\sin y \cos ^2 (xy) dy+e^x \cos^2 (xy) dx=0$

Question

$(a)\;\tan xy -\cos y=c \\ (b)\;\tan xy+e^x-\cos y=c \\ (c)\;e^x-\tan xy=c \\ (d)\;\sec xy-e^x- \sin y =c $