The correct answer is A. USB stands for Universal Serial Bus. It is a standard connection interface for connecting peripheral devices to computers. USB is a serial bus, which means that data is transmitted one bit at a time. USB is also a universal bus, which means that it can be used to connect a wide variety of devices, including keyboards, mice, printers, scanners, and external hard drives.
B. Universal Sequential Bus is not a correct answer because USB is not a sequential bus. A sequential bus is a type of bus in which data is transmitted one byte at a time. USB is a serial bus, which means that data is transmitted one bit at a time.
C. Unique Serial Bus is not a correct answer because USB is not a unique bus. USB is a standard connection interface that can be used to connect a wide variety of devices.
D. Unique Sequential Bus is not a correct answer because USB is not a sequential bus. A sequential bus is a type of bus in which data is transmitted one byte at a time. USB is a serial bus, which means that data is transmitted one bit at a time.