Tommy, don't play a joke _____ the little boy, he is very shy
A:at
B:on
C:to
D:for
①发源于落基山脉东坡 ②发源于阿巴拉契亚山脉西坡
③是密西西比河支流—俄亥俄河的支流 ④是美国水能资源最丰富的河流