Mother often _____ elder brother _____ little brother.        [ ]

A. mistake; for

B. mistook; as

C. mistakes; for

D. mistake; as

输送可燃流体介质、有毒流体介质，设计压力<1.0MPa，并且设计温度<400℃的GC2级工业管道属于GC2级工业管道。