Final answer:
The intensity of sunlight at Saturn is (1/9.5)² times the intensity on Earth, which is about 1/90.25 or 0.011 times the intensity on Earth, making answer A the correct choice.
Step-by-step explanation:
The intensity of sunlight at Saturn, which is 9.5 astronomical units (AU) from the Sun, can be calculated using the inverse square law. This law states that the intensity of sunlight decreases with the square of the distance from the source. Since Saturn is 9.5 times farther from the Sun than Earth, the intensity of sunlight it receives is (1/9.5)² times the intensity on Earth.
To find the exact value, we calculate (1/9.5)² which is approximately (1/90.25). Therefore, the correct answer to the student's question is A. 1/9.5 times the intensity on Earth, this actually means it is 1/90.25 or about 0.011 times the intensity on Earth, indicating that sunlight is much less intense on Saturn than it is on Earth.
Despite this weaker intensity, if we consider the apparent magnitude of the Sun from Saturn, it would still be the brightest star in the sky due to its enormous absolute magnitude compared to other stars.