These bags which, _____ to Hong Kong were missing at last. A. should have been sent B.should be sent C. should have sent D. should send 这题选A，但是我为什么一定要选择表示原本应该送去香港的意思呢？ 这些包裹应该送去香港的最后却丢失了也可以说得通啊，我觉得B也可以，求教老师解答，谢谢。