The correct answer is A Key Points 'The rise of the intellectuals has' should be there in place of 'The rise of the intellectuals have' The verb must match with the main subject of the sentence. Example: The quality of apples is good. Here the main subject is 'rise', so a singular verb should be used. Additional Information Substantial is an adjective which means large in amount or degree. Increase is a noun qualified by an adjective 'substantial' Normalisation means the process of bringing or returning something to a normal condition or state.. Example: The normalization of the situation will make the area more conducive to business activities The correct sentence is: The rise of the intellectual has led to a substantial increase in the normalisation of violence