There are no boot system commands in a router configuration in NVRAM.What is the fallback sequence that router will use to find an ios during reload?()
A、A.Flash,TFTP server,ROM
B、B.Flash,NVRAM,ROM
C、C.ROM,NVRAM,TFTP server
D、D.NVRAM,TFTP server,ROM
E、E.TFTP server,Flash,NVRAM