请选择ABCD5k1S0a/?(`5g You can’t pass the exam _________ you study hard.;z3v'I*k:I7]7~.b6N6N'`4a9d;K6|
A.if;z3v'I*k:I7]7~.b6N6N'`4a9d;K6|
B.because;z3v'I*k:I7]7~.b6N6N'`4a9d;K6|
C.unless;z3v'I*k:I7]7~.b6N6N'`4a9d;K6|
D.so;z3v'I*k:I7]7~.b6N6N'`4a9d;K6|