A 1972 agreement between Canada and the United States reduced the amount of phosphates that the municipalities had been allowed to dump into the great lakes.
a. same
b. reduced the phosphate amount that municipalities had been dumping.
c. reduces the phosphate amount municipalities have been allowed to dump.
d. reduced the amont of phosphates that municipalities are allowed to dump.
e. reduces the amount of phosphates allowed for dumping by municipalities.
I narrowed down to A and D. However, I don't understand how A is wrong. However, the municipalites are no longer allowed to dump phosphates as they used to and doesn't this qualify the use of Past perfect. I thought the use of HAD is required hear eventhough my ear told me to pick D. I need to master past perfect. Need help!