If the whole operation ________ beforehand, a great deal of time and money would have been lost.
句意：要是整个操作没有提前计划好的话，大量的时间和金钱都会被浪费。本题考查虚拟语气，与过去事实相反，主句用“would + have done”，从句用过去完成时。因此，本题的正确答案为C。