If $\big(\large\frac{2+\sin x}{1+y}\big)\frac{dy}{dx}$$=-\cos x,y(0)=1$ then $y\big(\large\frac{\pi}{2}\big)=$

Question

$(a)\;1\qquad(b)\;\large\frac{1}{2}$$\qquad(c)\;\large\frac{1}{3}$$\qquad(d)\;\large\frac{1}{4}$