What are the primary components of a linked list node?

• A. Data and a link to the previous node.
• B. Data and a link to the next node.
• C. Only data, no links.
• D. Data and a pointer to both previous and next nodes.

Answer: (B)

The essential idea is that a linked list node stores the value and a reference to the next node, allowing us to chain nodes together and traverse the list from one to the next. That makes data plus a link to the next node the best match, since the next pointer is what lets us move forward through the list. Having only a link to the previous node would not enable forward traversal on its own, and a node with only data has no connection to form a chain. A node that includes both previous and next pointers describes a doubly linked list, which is a valid design but adds extra pointers and memory beyond the basic singly linked list node.