The surface area of a sphere is same as the curved surface area of a right circular cylinder whose height and diameter are 10 cm each. The radius of the sphere is  Select the correct option.
A) 3 cm B) 5 cm C) 6 cm D) 8 cm E) none

Rationale: "solution 4 î r 2 = 2 î 5 x 10 â ‡ ’ r 2 = ( 5 x 10 / 2 ) â ‡ ’ 25 â ‡ ’ r = 5 cm . answer b"
Answer: B