Read the sentence, looking for clues
The Wankel engine had some effect on, or relation to, "automobile exhaust
emissions." Since it's described as an "engineering marvel," it must be a positive
effect. "But" at the beginning of the second clause is a detour roadsign, indicating
a change in direction, and "because" signals cause-and-effect: since the Wankel was
less fuel efficient than other types of engines, something happened to it in the
1970s, when "panic over fuel shortages" occurred.
Predict the answers
Since the sentence contrasts concerns over pollution and fuel efficiency, the
less-fuel-efficient Wankel engine "produced fewer" emissions but was "rejected" or
"modified" in the 1970s, when "concerns about" pollution were eclipsed by fuel
shortages.
Select the best matches from among the
choices
In the first blank, the best fit is (C)
substantially reduced.
(A) depended totally on is illogical in
context, and (B) preceded the problems
with is the opposite of what's needed; the fact that the Wankel
engine was "an engineering marvel" implies that it was developed in response to
problems with air pollution.
For the second blank, the best match is (F)
abandoned. (D) necessitated, meaning "required," is the
opposite of the prediction, since the Wankel engine was less fuel efficient than
other engines. The chronology of the sentence indicates that the Wankel engine was
(E) conceived, or "invented," before the
1970s.
For the third blank, (I) preoccupation with, or "obsession with," works
best. (G) ignorance of is the opposite of the prediction, and (H) espousal of, or "support for," doesn't make
sense when applied to pollution.
Confirm your answer by reading it into the
sentence
The Wankel rotary engine was an engineering marvel that substantially reduced automobile exhaust
emissions, but because it was less fuel efficient than the standard piston-cylinder
engine, it was abandoned in the early
1970s when preoccupation with pollution
gave way to panic over fuel shortages.
TAKEAWAY: Sometimes, the chronology of a sentence can help eliminate answer
choices.
