Which data structure allows for an unordered collection of unique objects?

• A. Map
• B. Set
• C. List
• D. Array

Answer: (B)

The choice of a Set stands out as it is specifically designed to hold an unordered collection of unique objects. In a Set, elements cannot be duplicated, meaning that each object is stored only once, which ensures the collection consists solely of distinct items. This characteristic is particularly useful when the uniqueness of elements is crucial, such as in scenarios involving membership tests or when eliminating duplicates from a dataset.

In contrast, a Map is a collection of key-value pairs where keys must be unique, but the values can be duplicated. Lists and Arrays, on the other hand, are ordered data structures that allow for duplicate entries, which does not meet the criteria of having unique objects. They maintain the order of insertion and do not inherently enforce uniqueness. Thus, the Set is the correct structure for an unordered collection of unique objects.