What does I/O stand for?

• A. Internal/Operations
• B. Interface/Output
• C. Output/Input
• D. Input/Output

Answer: (D)

I/O stands for Input/Output, describing how data moves between a computer system and its surroundings. This term covers both directions: input brings data into a system (like a keyboard, mouse, or reading from a file), and output sends data out (like a monitor display, printer, or network transmission). Using Input/Output highlights the two-way flow that enables programs to interact with users and other systems.

This is the best answer because it reflects the widely used, standard phrase that conveys both sides of data exchange. The other options don’t fit as well: Internal/Operations isn’t the conventional term for data flow; Interface/Output implies a specific interface and only one direction; Output/Input reverses the common order and isn’t the standard phrasing, even though the idea is similar.