Which description matches Linked Lists?

• A. A fixed-size contiguous array.
• B. A dynamic list that maintains a strict sequence with a single data type.
• C. A tree-based structure with pointers.
• D. An item list that allows for changing the number of values in a list as needed and can support multiple data types within the list.

Answer: (D)

Linked lists are a dynamic, non-contiguous way to store data where each element sits in a node that contains a value and a pointer to the next node. Because each node points to the next, you can add or remove elements by changing pointers, without moving a big block of memory. This lets the list grow or shrink at runtime, and it can even hold different kinds of data if the language supports generic or variant types.

The description that best matches this is one that highlights being able to change how many values are stored as needed and the possibility of holding multiple data types within the list. A fixed-size contiguous array doesn’t fit because it has a fixed capacity and contiguous memory. A tree-based description isn’t appropriate because a linked list is linear, not branching like a tree. And describing a dynamic list with a single data type misses the flexible, pointer-based structure that enables heterogeneity in some implementations.