Question

Of the following who has / have been troubled by the replacement of men by machanes ?

Answer 1

Answer:

Of the following who  have been troubled by the replacement of men by machines ?

Answer 2

Of the following who have been troubled by the replacement of men by machines?

• The verb 'trouble' is in its past tense form 'troubled' which indicates that the sentence is in the past tense.
• have is here used as a verb which denotes experiences, feelings, etc.

The correct word is 'have' for the given sentence.