命题“若ab=0,则a=0或b=0”的逆否命题是( )
A：若ab≠0，则a≠0或b≠0
B：若a≠0或b≠0，则ab≠0
C：若a≠0且b≠0，则ab≠0
D：若ab≠0，则a≠0且b≠0
Do the Smiths live next door to you? No, but they _________.
How old What colour Who does Is
