Six animals – K, L, M, S, T, U – must each be scheduled for examination by a veterinarian. The animals are to be examined one at time in six consecutive time slots on the same day according to the following conditions.      * M cannot be examined immediately before or immediately after S      * L must be examined immediately before U      * K must be examined fourth Which of the following is an acceptable examination schedule for the animals, in order from first to last?