For all x ,x is positive integer,"2-height" is defined to be the greatest nonnegative n of x, what is the greatest number of 2-height when 2n is the factor of x ?
A.2 B.12 C.40 D.76 E.90
什么叫, "2-height" is defined to be the greatest nonnegative n of x ??,这题又该怎么做,望赐教。谢谢!