请选择DCBA0b;h'e9D/@4W5f,f;V/q/z Don’t hurry.The bus won’t start _________ everybody gets on.4^,X)n1j.z+Z(g)B
A.since4^,X)n1j.z+Z(g)B
B.as4^,X)n1j.z+Z(g)B
C.until4^,X)n1j.z+Z(g)B
D.when4^,X)n1j.z+Z(g)B