(A) Because surveys revealed that the airline merger had confused public perceptions of the two brands - Correct.
(B) Because of confused public perceptions of the two brands, which had been revealed by surveys to be due to the airline merger, - Incorrect. Illogical and usage of 'which' is incorrect.
(C) Because public perceptions of the two brands from the airline merger have been confused, as revealed by a survey, - Incorrect. Change in Meaning.
(D) Due to confused public perceptions of the
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(B) Because of confused public perceptions of the two brands, which had been revealed by surveys to be due to the airline merger, - Incorrect. Illogical and usage of 'which' is incorrect.
(C) Because public perceptions of the two brands from the airline merger have been confused, as revealed by a survey, - Incorrect. Change in Meaning.
(D) Due to confused public perceptions of the
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