Which JSON data type is an unordered set of attribute-value pairs?

An array in JSON is an ordered list of values, enclosed in square brackets `[]`, not an unordered set of attribute-value pairs.

A string in JSON is a sequence of characters, representing a single value, not a collection of attribute-value pairs.

A JSON object is defined by curly braces `{}` and contains an unordered set of key-value pairs, where each key is a string and each value can be any valid JSON data type. This structure allows for representing complex data structures with named attributes.

A Boolean in JSON represents a true or false value, a single data point, not a collection.