A 1972 agreement between Canada and the United States reduced the amount of phosphate that municpalities had been allowed to dump into the Great Lakes.

A) reduced the amount of phosphates that municpalities had been allowed to dump
b) reduced the phosphates amount that municipalites had been dumping
c) reduces the phosphates amount municpalities have been allowed to dump
d) reduced the amount of phosphates that municpalities are allowed to dump
e) reduces the amount of phosphate allowed for dumping by municpalities



My question. There are no clues to to discern between A & D the answer is given as D but it might as well be A.

PLease help.

Thnx

There are always clues. You just have to find them. :)

You mentioned A and D, so I'll assume you know how to eliminate B, C, and E. Between A and D, the difference is the verb tense: "had been" (past perfect) vs. "are" (present).

Past perfect is used to indicate something that happened before something else - and because we are only given one sentence on SC, that other thing also needs to be in this sentence.

It might seem like we are saying "they used to be allowed to dump X amount and now they can dump Y amount" - two different things, right? But the sentence doesn't actually spell that out. It just mentions the one event. We don't have a second event or activity that occurs after... so we can't use past perfect.

The OG explanation tells you that present tense ("are") is appropriate to use here because it tells us that the state of affairs is still true today. And, yes, that's true... but the real way we know this is true is because we can find errors in the other choices, including A, so we know D must be right by default.

_________________
Stacey Koprince
Instructor
Director of Online Community
ManhattanGMAT

But cant we interpret it as follows
Two events
a) Signing of agreement
b) Amount X was allowed before the agreement was passed

So in this case since event b was before the signing of agreement, so can't we use Past Perfect in this case?

Thanks,
Amit

Amit, good question. In additional to Stacey's thorough explanation, the intended meaning of this sentence precludes your interpretation. It is nonsensical to believe that a past agreement could reduce the amount of phosphates that municipalities had been allowed to dump, since the dumping had already taken place. In other words, it is not possible to retroactively reduce the amount of dumping.

However, a similar sentence with a different meaning could definitely use the past perfect. For example, it would be grammatically proper to state A 1972 agreement between Canada and the United States fined the Canadians for the amount of phosphate that municipalities had dumped into the Great Lakes. . In this case, there are two distinct past events: the fine and the dumping. To indicate that the dumping preceded the fine, the past perfect is perfectly appropriate!

-dan