The three largest American airlines stunned the financial world by announcing a full-scale merger of their business, which created an alliance controlling more than 60 percent of all domestic air traffic.
A)
business,
which created an alliance controlling
"business" should be "businesses" since the alliance was created using three airlines businesses
"which" modifies business. It should be modify the action of "merging"
INCORRECTB)
businesses, creating an alliance that would control "creating an alliance that would control" mentions and modifies the result of the action in the previous clause
CORRECTC) businesses that created a
controlling alliance of
"controlling alliance" changes meaning from the original sentence.
INCORRECTD) business, and this alliance
controlledIncorrect use of past tense "controlled" It also changes meaning that this alliance once controlled and is no more controlling
INCORRECT E)
business that created an alliance that would control
"business" should be "businesses" since the alliance was created using three airlines businesses
"that" modifies business. It should be modify the action of "merging"
INCORRECTHence option B