Which statement best describes an advantage of linked lists over arrays?

• A. They allow dynamic growth and efficient insertion/deletion at arbitrary positions.
• B. They require contiguous memory blocks.
• C. They provide constant-time random access.
• D. They have fixed size.

Answer: (B)

Linked lists unlock growth and flexible editing because each node stands on its own with a pointer to the next (and possibly previous) node. This means you can add or remove elements by rewiring a few pointers, without having to move many other elements or require a single large contiguous block of memory. That dynamic size and the ability to splice in or out elements efficiently is the main advantage over arrays, which must allocate contiguous memory and often shift elements to insert or delete in the middle.

The statement about requiring contiguous memory blocks isn’t an advantage of linked lists—it describes arrays, which rely on a single continuous memory area. Constant-time random access isn’t a feature of linked lists either, since finding the k-th element usually requires traversing from the head, taking O(n) time in the worst case. And fixed size isn’t true for linked lists, since you can keep adding nodes to extend the list.