Newton's Cradle Consists of an Aligned Row of Identical Elastic

Multiple Choice

Newton's Cradle consists of an aligned row of identical elastic balls suspended by strings so they barely touch one another. When two balls are raised from one end and released, they strike the row and two balls pop out from the other end. If instead, one ball popped out with twice the speed of the two, this would violate

A) momentum conservation.
B) energy conservation.
C) both of these
D) none of these