It was an exciting moment for these fans this year, _____ for the first time in years they

saw their favorite singers. [ ]

A. that

B. which

C. when

D. while

下列各组中，加粗词语意思不同的两项是[ ]

A．公问其故／温故而知新，可以为师矣   

B．学而不厌，诲人不倦／贪得无厌   

C．肉食者鄙／先帝不以臣卑鄙   

D．二者不可得兼，舍身而取义者也／舍本逐末