What is the meaning of 'preventive detention'?

detaining persons on suspicion

The correct answer is Option 3- detaining persons on suspicion

Preventive detention laws allow for detaining persons on suspicion who have not been found guilty of any crime but their release may be detrimental to society like, they may commit more crimes if released or affect adversely investigations by the State or they are mentally ill and so on.

Preventive detention is granted under Article 22 of the Indian Constitution. However, Article 22 also contains safeguards to prevent abuse of this power. It states that a person who is detained under a preventive detention law must be informed of the grounds for detention, must be afforded the opportunity to consult and be represented by a legal practitioner, and must be produced before the nearest magistrate within a period of 24 hours of such detention. Additionally, the law provides that the detainee's case must be reviewed by an advisory board within three months of detention. These safeguards are intended to ensure that preventive detention is used only in exceptional circumstances and with due process.