If the length of the sides of two cubes are in the ratio 2:1, what is the ratio of their total surface area?  Choose the correct choice from the following.
A) 2 : 1 B) 3 : 1 C) 4 : 1 D) 6 : 1 E) 8 : 1

Rationale: "let x be the length of the small cube ' s side . the total surface area of the small cube is 6 x ^ 2 . the total surface area of the large cube is 6 ( 2 x ) ^ 2 = 24 x ^ 2 . the ratio of surface areas is 4 : 1 . the answer is c ."
Answer: C