A Level Computer Science OCR Practice Exam 2025 – Complete Study Resource

The correct answer is that a significant disadvantage of ROM is that it can become clogged up and has limited storage size. ROM, or Read-Only Memory, is a type of non-volatile memory that retains its contents even when the power is turned off. This characteristic means that it is not subject to the same limitations as volatile memory, which loses its data when power is lost.

The limited storage size of ROM is significant because it is generally used to store firmware or software that is not intended to be modified frequently. As software and data requirements grow, the fixed and relatively small capacity of ROM can become a bottleneck. If the ROM becomes "clogged," there may not be enough space to store necessary updates or additional programs, making it less adaptable compared to other memory types such as RAM.

Furthermore, while the other options present certain concerns, they do not represent fundamental disadvantages of ROM as directly as the issue of limited storage capacity and the inability to easily expand its content. Volatility is not applicable to ROM, security concerns can vary, and access speeds compared to RAM may not necessarily affect its primary role within a computer system.