The expected rise in the price of oil could be a serious impact to

Hi, there. I'm add my two cents to this discussion.

The expected rise in the price of oil could be a serious impact to industrialized nations and severely diminish the possibility to have an economy free of inflation.
(A) be a serious impact to industrialized nations and severely diminish the possibility to have
(B) seriously impact on industrialized nations and severely impede the possibility to have
(C) seriously impact on industrialized nations and severely impede the possibility of having
(D) have a serious impact on industrialized nations and severely impede the possibility to have
(E) have a serious impact on industrialized nations and severely diminish the possibility of having

As I read the prompt, two things grated on me --- "a serious impact to . . ." and "the possibility to . . . ." Those are both wrong.

To eybrj2, I would say: I don't know who says that "impact" should not go with "on", but those people are wrong. If the verb "to impact" is going to be followed by a preposition, the preposition "on" is the exact right one. That's the correct idiom.

Another correct idiom is the word "of" following "probability". We speak of a "probability of" something, not a "probability to" something.

Just with those two issues, here are the answer choices:
(A) be a serious impact to industrialized nations and severely diminish the possibility to have
(B) seriously impact on industrialized nations and severely impede the possibility to have
(C) seriously impact on industrialized nations and severely impede the possibility of having
(D) have a serious impact on industrialized nations and severely impede the possibility to have
(E) have a serious impact on industrialized nations and severely diminish the possibility of having

That leaves (C) and (E). Then we get to that funny word "impede."

First of all, "impede" means to hinder, to put up obstacles in front of. The word "diminish" means to make less.

Probability is an abstract mathematical thing --- ultimately, it's a number. One can make this number more or less, but something is quite bizarre about the idea of impeding a number. It's like being told that a football player tackled the number pi --- it just doesn't make sense.

Furthermore, to "diminish the probability of X" is idiomatic, whereas there's something inherent wrong/awkward/strange about "impede the probability of X."

That means (C) is out also, so (E) is the only choice remaining that is free of all mistakes and awkwardness. Answer = (E)

Does all this make sense?
Here's another SC question with some similar issues.
https://gmat.magoosh.com/questions/1160
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Let me know if anyone reading this has any additional questions.

Mike