Which data structure is best for FIFO processing?

• A. Stacks
• B. Arrays
• C. Queues
• D. Linked lists

Answer: (C)

FIFO processing means handling items in the order they arrive. The structure designed for that is a queue: you add new items at the back (enqueue) and remove from the front (dequeue), so the oldest item is processed first. This matches workflows like print queues or task dispatch where you don’t want newer items to jump ahead of older ones.

Storing items in a stack happens in a last-in, first-out order, which would process the most recently added item first, not the oldest. Arrays are just containers; implementing a FIFO queue with an array can work but requires extra bookkeeping and can be inefficient if you have to shift elements or manage indices. Linked lists can be used to implement a queue, but the data structure that inherently provides FIFO behavior is the queue itself.