Step 1: Understanding the Concept:
The question asks about a 'unique preventive measure' mandated by the POCSO Act. This refers to a specific duty or obligation created by the Act to help prevent or report crimes against children.
Step 2: Detailed Explanation:
Let's analyze the provisions:
(A) Mandatory reporting by all citizens: This is a unique and critical preventive measure under the POCSO Act. Section 19(1) of the Act makes it mandatory for any person (including a child) who has an apprehension that a child is likely to be subjected to sexual abuse or has knowledge of such an offense, to report it to the Special Juvenile Police Unit or the local police. Failure to report is a punishable offense under Section 21. This places a legal duty on every citizen.
(B) Digital surveillance: The Act does not mandate general digital surveillance.
(C) Background checks for all professionals: While many institutions dealing with children have adopted background checks as a best practice (and it is a requirement under the JJ Act for childcare institutions), the POCSO Act's most distinctive feature is the universal mandatory reporting requirement.
(D) Psychological profiling of children: This is not a provision of the Act. The focus is on the offender's actions and the protection of the child, not profiling the child.
Step 3: Final Answer:
The mandate for every citizen to report any apprehension or knowledge of a sexual offense against a child is a unique and powerful preventive measure enshrined in the POCSO Act.