Solution: A. When the position of the convex lens remains unchanged, the candle moves to the right and the light screen moves to the right to get a clear image. In the experiment, only the candle moves to the right, the positions of the convex lens and the light screen remain unchanged, and the image is on the right side of the light screen. Hyperopia glasses are convex lenses, which can converge light, so that the converged imaging light can be converged in advance, and the light screen can receive clear images. This fits the problem.

B in the experiment, only the candle is moved to the right, and the positions of the convex lens and the light screen remain unchanged, like on the right side of the light screen. Short-sighted glasses are concave lenses, which have divergent effects on light, causing the converged imaging light to be misconverted, making the image farther away from the light screen, and making the image not received on the light screen.

C. As shown in the figure, the refracted rays AO and BO converge at the imaging point o. When the transparent glass is placed in front of the convex lens, the refracted rays are refracted twice by the transparent glass and converge at the o' point, and the image point moves to the right, so that the image cannot be received on the screen.

D, the plane mirror can't transmit light, and the image can't be received on the light screen.

So choose a.