According to the first law of illumination, the illumination of a surface due to a source of light is

• A. Inversely proportional to the distance between the surface and the source of light
• B. Inversely proportional to the square of the distance between the surface and the source of light
• C. Directly proportional to the distance between the surface and the source of light
• D. Directly proportional to the square of the distance between the surface and the source of light