The sentence has four underlined words or phrases. Choose the word or phrase that must be changed for the sentence to be correct. The ways of communicationhas changed dramaticallysince the last century.
The correct option is B has The sentence begins with 'the ways of' which indicates the plural nature of 'communication'. The verb to be used with plural nouns is 'have'. 'Has' is used in singular cases. Therefore, the incorrect word is 'has' and the correct answer is option B).
The other words in the remaining options are used in the correct form and tense and so need not be changed for the sentence to be correct.