In the following question, a sentence has been given in Active/Passive voice. Out of the four alternatives suggested, select the one which best expresses the same sentence in Passive/Active voice. The police arrested him on suspicion.

• Arresting him on suspicion has been done by the police.
• On suspicion the police had been arresting him.
• He was arrested on suspicion by the police.
• He has had been arrested on suspicion by the police.