UmangMathur wrote:
According to a recent study, Earth's magnetic north pole is moving away from Alaska and toward Siberia so rapidly, within 50 years, that the swirling green auroras of the Northern Lights might be visible in cities as far south as Rome, which is located at 41º north latitude.
(A) rapidly, within 50 years, that the swirling green auroras of the Northern Lights might be visible in cities as far south as Rome, which is
(B) rapidly, within 50 years, people may be able to see the swirling green auroras of the Northern Lights in cities as far south as Rome and
(C) rapidly that, within 50 years, the swirling green auroras of the Northern Lights may be visible from cities as far south as Rome,
(D) rapidly such that, within 50 years, people might be able to see the swirling green auroras of the Northern Lights from cities as far south as Rome, and
(E) rapidly that, within 50 years, the swirling green auroras of the Northern Lights might be visible by people in cities far to the south; such as Rome,
OFFICIAL EXPLANATION
This sentence reports the striking findings of a research study: Earth's magnetic north pole is moving so fast that the Northern Lights may be visible from new locations within 50 years. The modifier
within 50 years describes something that will happen in the future, so it cannot be referring to the fact that the
north pole is (now)
moving in a certain way. Rather, it must describe the study's conclusion that the Northern Lights will be visible from other locations in future.
(A) The modifier
within 50 years illogically describes the present movement of Earth's magnetic north pole rather than the predicted future outcome.
(B) In this sentence,
Earth’s ... rapidly and
people ... latitude are both complete sentences, creating two problems. First, the overall construction is a run-on sentence, containing no conjunction to properly connect the two sentences. Second, the placement of
within 50 years between the two clauses makes it unclear what that phrase is intended to describe. Finally, the use of
and at the end of this choice makes the meaning redundant, since "as far south as Rome" and "at the same latitude as Rome" are identical concepts.
(C) CORRECT. In this sentence,
within 50 years is properly used to describe what will happen in the future.
As far south as Rome is idiomatically correct, and the final modifier correctly describes Rome.
(D) The combination of
so and
such is redundant and unidiomatic. The use of and at the end of this choice makes the meaning redundant, since "as far south as Rome" and "at the same latitude as Rome" are identical concepts.
(E) The construction
visible by people is unidiomatic and should be phrased as
visible to people. The part of this sentence following the semicolon is a modifier, not a complete sentence (independent clause), thus creating a sentence fragment.