1. Choice questions. ( 3 points for each) 1.The word length of the microcomputer is O A. Binary bits that the computer can directly process at a time B. Width of CPU data bus C. The length of one byte D. Width of CPU address bus 2. The interrupt vector refers to 0 . A. The starting address of the selected device B. The starting address of the transmitted data C. Entry address of interrupt service routine D. The breakpoint address of the program 3.The control bus of the CPU provides 0 . A. Data Signal Flow B. Timing and control signals for all memory and I/O devices C. Response signals from I/O devices and memory D. Both B and C 4.When transferring data, the transfer method that takes the longest CPU time is O. A. Inquiry B. Interruption C. DMA D. Unconditional transmission 5 .When peripherals are addressed with 0 , no special set of I/O instructions is required. A. Uniform Addressing Law B. Independent addressing method C. both D. neither