The differential equation for y = A cos αx + B sin αx,

The differential equation for y = A cos αx + B sin αx, where A and B are arbitrary constants is

(A) $\frac{d^{2} y}{d x^{2}}-\alpha^{2} y=0$

(B) $\frac{d^{2} y}{d x^{2}}+\alpha^{2} y=0$

(C) $\frac{d^{2} y}{d x^{2}}+\alpha y=0$

(D) $\frac{d^{2} y}{d x^{2}}-\alpha y=0$