Q. Fill in the blank by choosing from the options given. He is suspicious ________ all his neighbours.

Explanation:

The correct collocation is ‘suspicious of’ when referring to people: ‘He is suspicious of all his neighbours.’ ‘From’ indicates origin and does not collocate with ‘suspicious.’ ‘Before’ relates to time or position and is incorrect here. ‘None of the above’ is therefore wrong. Note: ‘suspicious about’ can be used for situations, but with a person we use ‘of.’