问一道OG上的句子对等题

wtttopUID: 3913556

21、The plan, which the engineers said would save the aquifer by reducing pumping
to __________ levels, has passed a governmental environmental review but faces
opposition from outdoor and environmental groups.
A innocuous
B feasible
C practicable
D minimal
E remedial
F benign
请问为什么选bc啊？  不太懂这句话。这个方案是降低泵水到可行的水平？然后说的是这个方案通过了政府核查，但是被环保组织反对。不懂这句话的逻辑。pumping指的是泵水的意思吗？求大神们指点~~~谢谢~~~