What data structure is a collection of elements where each element has a specific index?

The correct answer is an array. An array is a data structure that stores a collection of elements, each identified and accessed by a specific index. This structure allows for efficient retrieval and manipulation of elements since each index directly points to its corresponding value within the array.

While a list is also a collection of elements and can utilize indices, it typically provides more flexibility, allowing for varied data types and dynamic resizing, which can sometimes obscure the connection between indices and elements. In contrast, an array is more rigid, meaning all elements are of the same type, and it uses fixed-size storage.

Sets, on the other hand, do not have indices associated with their elements; they are unordered collections that ensure each element is unique. Similarly, dictionaries store key-value pairs rather than indexed elements, making them more suited for associative data rather than sequential access.

In summary, arrays are specifically characterized by their indexed access to elements, differentiating them from lists, sets, and dictionaries.