What data structure processes items in first-in-first-out order?

What data structure processes items in first-in-first-out order?

• A. Queue
• B. Stack
• C. Hash Table
• D. Linked List

Answer: (A)

First-in-first-out processing is the hallmark of a queue. A queue enqueues items at the rear and dequeues from the front, so the oldest item added is the first to be processed. This makes it ideal for ordered workflows like print queues or task scheduling where arrivals should be handled in the order they came in. A stack uses last-in-first-out, so the most recently added item is handled first. A hash table doesn’t keep a predictable order, and a linked list can be traversed in any order depending on how you use it, but neither guarantees FIFO on their own.

First-in-first-out processing is the hallmark of a queue. A queue enqueues items at the rear and dequeues from the front, so the oldest item added is the first to be processed. This makes it ideal for ordered workflows like print queues or task scheduling where arrivals should be handled in the order they came in. A stack uses last-in-first-out, so the most recently added item is handled first. A hash table doesn’t keep a predictable order, and a linked list can be traversed in any order depending on how you use it, but neither guarantees FIFO on their own.