If a*b denotes the greatest common divisor of a and b, then ((12*16)*(18*12)) = ?	Choose the correct choice from the following choices.
A) 24 B) 12 C) 6 D) 4 E) 2

Rationale: "the greatest common divisor of 12 and 16 is 4 . hence 12 * 16 = 4 ( note that * here denotes the function not multiplication ) . the greatest common divisor of 18 and 12 is 6 . hence 18 * 12 = 6 . hence ( ( 12 * 16 ) * ( 18 * 12 ) ) = 4 * 6 . the greatest common divisor of 4 and 6 is 2 . answer ; e ."
Answer: E