4.i think my long and active life---due to the healthy life

4.i think my long and active life___due to the healthy life i lice.
a.must be
b.can be
c.must have been
d.can have been
5.shall we go skating or stay at home?which __do yourself?
a.do you rather
b.would you rather
c.will you rather
d.should you rather
6.i stayed at hotel while in new york
oh,didi you?you__with barbara.
a.could have stayed
b.could stay
c.would stay
d.muust have stayed
test 12