A Mass, M, Slides Down a Frictionless Incline and Hits $\theta$

Multiple Choice

A mass, m, slides down a frictionless incline and hits a spring with spring constant k. Find the spring compression when the acceleration of the mass is zero.

A) mg/k
B) mg cos $\theta$ /k
C) mg sin $\theta$ /k
D) mgh sin $\theta$ /(kx)
E) None of the above statements is correct.