It has often been assumed that if governments limit fishing, the numbers of fish will increase, but in the case of fish such as salmon such a recovery can come about much more readily if governments were to order the removal of the dams that limit the water-flow required by spawning fish.
(A) can come about much more readily if governments were to order the removal of the dams that limit the water-flow required by spawning fish.
If governments were (Past tense)....., such a recovery can (present tense ) . Eliminate
(B) would come about much more readily if governments order the removal of the dams that limit the water-flow that spawning fish requires.
if governments order(Present tense)....., such a recovery would(Past tense).....
(C) came about much more readily if governments would order the removal of the dams that limit the water-flow required by spawning fish.
came about . How such a recovery already came . This is a conditional statement . If ....., then ...... So, Using came here is appropriate. Eliminate
(D) might come about much more readily if governments were to order the removal of the dams that limit the water-flow required by spawning fish.
Good
(E) would have come about much more readily if governments ordered the removal of the dams that limit the water flow that fish need in order to spawn.
Good in terms of If and then. But there other issues. water flow - error, in order to spawn - meaning error. Eliminate.
D must be the OA.
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