According to the inverse square law, if the distance from the x-ray source to the receptor is doubled, the beam intensity at the receptor becomes:

Giải thích

The inverse square law states that intensity is inversely proportional to the square of the distance, so doubling the distance reduces intensity to one-fourth. Halving the intensity would correspond to a different relationship that the law does not describe. Intensity decreases rather than increases as distance grows, so the options describing greater intensity are incorrect.