A:A⊆B
B:B⊆A
C:A∩∁RB=R
D:A∩B=∅
— Mike, what's your favourite hobby? — ____ (surf). It's exciting.
已知一次函数y=kx+b,y随着x的增大而减小,且kb>0,则这个函数的大致图象是( ).