Official Solution:While compiling the National Ocean and Atmospheric Administration spill report, scientists have concluded that although measuring seven times that of Exxon-Valdez, the spill in Gulf, caused by a fractured concrete core – Nitrogen gas was used to accelerate the curing of the concrete mixture, thereby weakening the core – the Gulf-spill may have caused less damage. A. although measuring seven times that of Exxon-Valdez, the spill in Gulf, caused by a fractured concrete core
B. although the spill in Gulf, caused by a fractured concrete core, measured seven times that of Exxon-Valdez
C. measured seven times that of Exxon-Valdez, the spill in Gulf was caused by a fractured concrete core
D. caused by a fractured concrete core, the spill in Gulf measures seven times that of Exxon-Valdez
E. although the spill in Gulf, measured seven times that of Exxon-Valdez, was caused by a fractured concrete core
It is better to introduce the subject the spill in gulf early in the sentence, so as to make the comparison with that of Exxon-Valdez clear. Using two subjects, the spill in Gulf and the Gulf-spill, for the same verb may have caused is ungrammatical.
(A) Redundant subjects (the spill in Gulf and the Gulf-spill) for the verb may have caused.
(B) CORRECT. Fixes the above issue: The subject the spill in Gulf refers to the verb measures and the subject the Gulf-spill refers to the verb may have caused. The conjunction although correctly contrasts measures seven times that of Exxon-Valdez with may have caused less damage.
(C) Run-on sentence: Two main clauses (the spill in Gulf was caused by a fractured concrete core and the Gulf-spill may have caused less damage) joined without proper conjunction or punctuation. Undue importance on the explanatory clause caused by a fractured concrete core.
D. Run-on sentence: Two main clauses (the spill in Gulf measures seven times that of Exxon-Valdez and the Gulf-spill may have caused less damage) joined without proper conjunction or punctuation. Undue importance on the explanatory clause caused by a fractured concrete core.
E. The conjunction although wrongly contrasts was caused by a fractured concrete core with may have caused less damage.
Note 1: Why B is better than E? Because of the word "although", a contrast should be depicted between the dependent clause and the independent clause:
Option E: Dependent clause: although the spill in Gulf, measured seven times that of Exxon-Valdez was caused by a fractured concrete core.
Independent clause: the Gulf-spill may have caused less damage.
There is no contrast between the two clauses.
Option B: Dependent clause: although the spill in Gulf, caused by a fractured concrete core, measured seven times that of Exxon-Valdez
Independent clause: the Gulf-spill may have caused less damage.
Proper contrast is established.
Note 2: The segment between the two dashes: Two dashes act as a set of parentheses. The part within the two dashes is not grammatically related to the main sentence, but an interruption to provide some additional information.
Answer: B