Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year.
A. Air traffic routes over the North Pole are currently used by only two or three planes a day, but it was found by a joint Canadian–Russian study to be both feasible as well as desirable if those routes are opened to thousands more commercial planes a year. X
Error 1: “but”…the use of but to indicate a contrast is not required
Error 2: “both feasible as well as desirable” breaks the idiom both X and Y
B. Currently used by only two or three planes a day, a joint Canadian–Russian study has found that if air traffic routes over the North Pole are opened to thousands more commercial planes a year, it would be both feasible and desirable. X
Error: Meaning – ‘a joint study is NOT used by two or three planes a day…that makes no sense
C. A joint Canadian–Russian study, finding it to be both feasible as well as desirable to open air traffic routes over the North Pole, which are currently used by only two or three planes a day, to thousands more commercial planes a year. X
Error 1: This ‘sentence’ lacks a main verb
Error 2: ‘which’ is modifying North Pole …suggesting that the North Pole is used by only two or three planes a day
D. Although air traffic routes over the North Pole are currently used by only two or three planes a day, a joint Canadian–Russian study has found that opening those routes to thousands more commercial planes a year is both feasible and desirable.
Correct
E. With air traffic routes over the North Pole currently used by only two or three planes a day, opening those routes to thousands more commercial planes a year has been found by a joint Canadian—Russian study as both feasible and desirable X
Error: “With…, opening” ? So in other words, opening those routes and “with air traffic routes” ? Makes no sense.
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