Solution

The correct answer is A and D Only

Key Points

• Statement A is false because the processor does not have direct access to secondary memory. It directly interacts with primary memory (also called main memory) and cache memory. For information on the secondary storage, it goes through input/output routines.
• Statement D is false because memory system is not implemented on a single level memory. Computer systems have a memory hierarchy which includes various levels like registers inside CPU, cache memory, main memory and secondary memory. Each level in the hierarchy represents a trade-off between speed and size, with the memory getting slower and larger as one moves from registers to secondary memory. This structure helps in optimizing system performance.
• Statements B and C are true, B is true because primary memory (like RAM) indeed stores the active instructions and data for the program being executed on the processor.
• C is true because secondary memory (like hard disks, SSDs) is often used for long-term storage and can serve as a backup. It stores the data and instructions that are not actively being used by the processor.

Additional Information

• Primary Memory: Primary memory, also known as main memory, is the component in a computer that holds data while it is being processed. Its main characteristics are:
  • It is directly accessible by the CPU.
  • Stores data temporarily.
  • It is volatile, which means data is lost when power is turned off.
  • It contains information that's currently being used by the computer, such as operating system instructions, applications in use, and the data they use.
  • Examples include Random Access Memory (RAM), and cache memory.
• Secondary Memory: Secondary memory, also referred to as external memory or auxiliary storage, is where a computer permanently stores data, until it is deliberately removed. Its main characteristics are:
  • It is not directly accessible by the CPU. The computer uses I/O channels to access secondary memory.
  • Stores data permanently, even when the computer is powered off.
  • It is non-volatile, which implies that it retains information even when not powered.
  • Used for storing the bulk of the computer's data, such as operating system files, applications, and user files.
  • Examples include Hard Disk Drives (HDDs), Solid State Drives (SSDs), and external hard drives.