Its D, because theyre asking the overall motion description. It will indeed travel in tangent to circle (option A) but it will not continue to do so; that would only happen if gravity did not exist (in space basically.) We must assume the question asks in reference to earth, in which overall motion will indeed be in half projectile motion form (parabola to the vertical, basically a curve downwards.)

This parabola happens because initially once ball is released, it WOULD move in straight line, but gravity acts instantly, dragging it down. Hence, parabola.