The correct answer is: C. Buffer
A buffer is a temporary storage location that is used to compensate for the difference in rates of flow of data from one device to another. It is used to store data that is being transferred between two devices, such as a computer and a printer, or a computer and a hard drive. The buffer allows the devices to operate at different speeds without causing data loss or errors.
A cache is a type of buffer that is used to store data that is frequently accessed. This can improve the performance of a computer by reducing the number of times that data needs to be read from the main memory.
A concentrator is a device that is used to connect multiple devices to a single network. It does not store data, but it does provide a way for the devices to communicate with each other.
An I/O device is any device that can be used to input or output data to or from a computer. This includes devices such as keyboards, mice, printers, and scanners.
E is not the correct answer because it is not a type of storage device.