Johanna waited at the bus stop for nearly an hour ___ the bus finally arrived.

A. when        B. unless        C. before        D. after

Johanna waited at the bus stop for nearly an hour ___ the bus finally arrived.

 Johanna waited at the bus stop for nearly an hour ___ the bus finally arrived.

A. when           B. unless             C. before             D. after

Johanna waited at the bus stop for nearly an hour ___ the bus finally arrived．

A．when          B．unless            C．before           D．after