Sentence Correction

Even though the state has spent ten years and seven million dollars planning a reservoir along the Ubi River, the project will have to be abandoned as a result of the river becoming so heavily polluted.

(A) will have to be abandoned as a result of the river becoming so heavily polluted
(B) is to be abandoned on account of the heavy pollution which the river received
(C) had to be abandoned because the river had received such heavy pollution
(D) has to be abandoned because of the river and its heavy pollution
(E) must be abandoned because the river has become so heavily polluted

[spoiler]OA E but what is meaning of So heavily polluted
Don't you have problem with So[/spoiler]

I too agree with E. you can go through the differences between "Although", "Even though" and "inspite of"... you'll know why the option E is correct. Although all three convey the same meaning "Even though" is considered a strong word when compared to "although" and "inspite of". Also "The project" is singluar so elimniate option A. And C too as past participle "had" is unnecessary. Remaining option b,d,e out of all these three I find option E to be the strongest("must")and thus the answer...besides b is awkward.

IMO: E