In the question, one sentence is given and four words are given in bold denoted by (A), (B), (C) and (D). You have to decide which of the following is inappropriate in context. If all the words are appropriate in the context then mark ‘All correct’ as your answer.

Apart from its tremendous (A) role in the development (B) of tourism in Ontario province (C) in Canada and Northern part of the US, Niagara Falls became a significant (D) source of energy.