IGDTUW 2026 — Computer PYQ

The correct option is (c) External Hard Disk.

Detailed Solution & Explanation

In computer systems, memory is classified into different categories based on access speed, cost, volatility, and purpose. Storage devices used for backup must be non-volatile (retaining data even when the power is turned off) and typically portable or high-capacity so they can store copies of data safely outside the primary system.

Analyzing the Options:

• (a) Cache Memory: A high-speed, volatile primary memory located close to the CPU. It temporarily stores frequently used instructions and data to speed up processing. It cannot be used for backup because it loses all data when powered off.

• (b) RAM (Random Access Memory): The main memory of the computer. It is volatile and holds data that the CPU is actively using. Once the computer is turned off, everything in RAM is erased.

• (c) External Hard Disk: A non-volatile, secondary storage device. Because it is portable, durable, and offers large storage capacities, it is primarily used to create copies of critical files, system images, and data backups safely away from the computer's internal drive.

• (d) CPU Register: Extremely small, ultra-fast internal storage locations inside the processor itself. They only hold binary values or instructions for immediate execution by the ALU.

Therefore, an External Hard Disk is the only logical choice suitable for backup storage.