Which of the following is an example of short term memory in a computer?

RAM, or Random Access Memory, is the correct answer because it functions as the primary short-term memory in a computer. When a computer is running applications or processes, the data that is actively being used by the CPU is stored in RAM. This allows for quick access and manipulation of the data, facilitating smooth operations and efficient performance. Unlike long-term storage solutions, which retain data even when the power is off, RAM is volatile and loses its contents when the computer is turned off.

The other components mentioned do not serve as short-term memory in the same way that RAM does. The hard drive is a type of long-term storage, designed for permanent data retention, and accessing data from the hard drive is significantly slower compared to RAM. The external data bus is a communication pathway that transfers data between the CPU and other components, while registers are small storage locations within the CPU used for quick access to data the CPU is currently processing. While registers are indeed part of the short-term memory hierarchy, RAM serves a larger role in storing temporary data for active sessions, making it the better example in this context.