A convex lens forms a real image of a point object placed on its principal axis. If the upper half of the lens is painted black,

If the upper half of the convex lens is painted, then only the intensity of the image will decrease because the amount of light passing through the lens will decrease. Also, there will be no shift in the position of the image since all the other parameters like distance between the lens and the object, focal length etc. remains the same.

Hence, option C and D are correct.