target2015
The Cygnus spacecraft was grounded last week ahead of its launch date due to giant coronal mass ejections from the Sun, which raised radioactivity to such levels so that their avionics systems might malfunction and the navigability of the ship might be compromised.
A. due to giant coronal mass ejections from the Sun, which raised radioactivity to such levels so that their avionics systems might malfunction
B. due to giant coronal mass ejections from the Sun, thereby raising radioactivity to such levels that their avionics systems might malfunction
C. because the Sun had ejected giant coronal mass, which had raised the radioactivity to levels such that its avionics systems would malfunction
D. because of coronal mass ejections from the Sun raising the radioactivity to levels so high as to lead its avionics systems to malfunction
E. because giant coronal mass ejections from the Sun had raised the radioactivity to such levels that its avionics systems might malfunction
OFFICIAL EXPLANATION:
Creating a filter: We read the prompt. Supposing that we try the universal checks of subject and verb, and intended meaning, and we don't find an error, we can proceed to the answer choices and evaluate them exhaustively, skipping answer choice (A) initially.
Finding objective defects: In (B), "thereby raising" sounds funny and distorts the meaning of the sentence. It makes it sound like the spacecraft raised the levels. So (B) is out.
In choice (C), the construction at the beginning sounds weird. We look for a more objective problem and find it: it says "systems would malfunction," which is not parallel with the following "might be compromised." The intended meaning is that if one happens, the other will happen. Therefore, (C) is out.
Choice (D), similarly to (C), is not parallel due to the verb "to malfunction." So it's out.
That leaves us with (E), which sounds pretty good, and (A). We try to find a more objective difference and find it in the pronouns, "their avionics systems" and "its avionics systems." The avionics systems belong to the spacecraft, which is grammatically singular, so answer choice (A) is flawed.
The correct answer is (E).