Question

examination are an incentive ___________ diligence​

Answer 1

Examination are an incentive to diligence​.

Explanation:

• Preposition is the word which can connects the nouns, pronouns and verbs to give a complete meaning of a sentence.
• Here, it is clear from the question that the diligence is increased by the having examinations.
• Here 'to' is the appropriate preposition word which can be used. Other than "to", no other preposition words are used because it may change the sentence meaning.

To know more:

She takes a lot of trouble ___ her work.  Fill with preposition

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