i'm to tired ,so i(D ) sit down and rest every five minutesA,.must Bmust to C.have D.have to为什么选D 为什么不选A.B.C

x��RIo�@�+s#������U}`8�z3���+��.-�XY�`��~��Կ��@�R�J����7��F�G�P�h9��%M��Q���U��s/�$�M��RԈr�^���B2j�DS����9�N�?$!�Ha;)^ZΛ/