How are sets different from lists?

• A. Sets are ordered; lists are unordered
• B. Sets allow duplicate elements; lists do not
• C. Sets do not allow duplicate elements; lists do
• D. Sets and lists are identical in functionality

Answer: (C)

Sets in Python are designed to hold unique elements, meaning that they do not allow any duplicate values. This characteristic sets them apart from lists, which can contain multiple instances of the same element. When elements are added to a set, any duplicates are automatically ignored, ensuring that each item is stored only once.

This distinction is crucial when it comes to operations that require uniqueness, such as when you need to remove duplicates from a collection of items or perform mathematical operations like unions and intersections where unique elements are needed. In contrast, lists maintain the order of elements and allow for duplicates, which can be useful in many different scenarios.