If the operation € is defined for all x and y by the equation x € y = 2*x*y, then 6 € (4 € 5) =  Select the correct option
A) 480  B) 120  C) 160  D) 240  E) 360

Rationale: working inside out , ( 4 € 5 ) = 2 * 4 * 5 = 40 6 € 40 = 2 * 6 * 40 = 480 hence , answer is a
Answer: A