Which type of computer memory holds only the program and data that the CPU is currently processing?

Introduction / Context:
Computer systems use several different types of memory, each with its own purpose. Some memory stores configuration data, some stores firmware, and some holds active programs and data that the processor works on during execution. Understanding which memory type plays which role is basic computer knowledge. This question asks you to identify the memory that temporarily holds the program and data that the CPU is currently processing.

Given Data / Assumptions:
- The question focuses on the program and data that are actively being processed by the CPU at a given moment.
- Options include CMOS memory, ROM, RAM, and ASCII storage.
- We assume a standard Von Neumann architecture where instructions and data share the same memory space in main memory.

Concept / Approach:
RAM, or Random Access Memory, is the main working memory of a computer. It stores the instructions of running programs and the data they are using so that the CPU can fetch and execute instructions rapidly. RAM is volatile, meaning that its contents are lost when power is turned off. ROM, or Read Only Memory, stores firmware such as the system BIOS and does not normally change during regular operation. CMOS memory is used to store configuration settings like date, time, and hardware options. ASCII refers to a character encoding scheme, not a physical memory type. Therefore, the memory that holds the currently processed program and data is RAM.

Step-by-Step Solution:
Step 1: Recall that RAM is described as main memory or primary memory and is directly accessible by the CPU for reading and writing. Step 2: Recognise that running applications are loaded from secondary storage, such as hard drives, into RAM before the CPU can execute their instructions. Step 3: Understand that ROM stores fixed instructions used for bootstrapping and firmware, not the changing programs and data of everyday tasks. Step 4: Note that CMOS memory is a small non volatile area for system configuration, not for large program and data storage. Step 5: Recognise that ASCII is an encoding for characters and not a type of memory hardware at all. Step 6: Conclude that the correct answer is RAM, which is the memory that holds only the program and data that the CPU is currently processing.

Verification / Alternative check:
Computer architecture texts explain that the CPU fetches instructions from main memory, which is implemented as RAM chips. They describe the process of loading a program from disk into RAM and then running it. ROM is described separately as firmware storage, often with examples like BIOS code. CMOS memory is discussed only in the context of small configuration information. ASCII appears in chapters on data representation rather than hardware. This clear separation of roles confirms that RAM is the memory type that matches the description in the question.

Why Other Options Are Wrong:
CMOS configuration memory: Stores system setup parameters and clock information, not the active program code and data used during normal computation.
ROM (Read Only Memory): Contains firmware and bootstrap code that rarely changes, rather than the constantly changing content of running programs.
ASCII character storage: ASCII is a code for characters; it is not a type of physical memory device and cannot by itself hold running programs.

Common Pitfalls:
Students sometimes confuse memory and storage or believe that ROM stores currently running programs because it contains critical system code. Another pitfall is to associate CMOS memory with general system memory because both terms appear in BIOS discussions. To avoid these errors, focus on the dynamic nature of the data described. The question mentions the program and data that the CPU is currently processing, which by definition must be in read write memory, and that is precisely what RAM provides.

Final Answer:
The type of computer memory that holds only the program and data that the CPU is currently processing is RAM (Random Access Memory).