Correct option is B
Given:
Radius of the smaller sphere = 5 cm
Radius of the larger sphere = 15 cm
Formula Used:
Surface Area of a sphere
Ratio of Surface Areas =
Solution:
Ratio of radii = = 3
Ratio of Surface Areas = = 9
The surface area of the larger sphere is 9 times greater.
Final Answer
So the correct answer is (b)