食源性疾病主动监测中用于病毒检测的粪便样本采集后30min内放入（）冰箱中。
A.2-4℃
B.0℃
C.-20℃
D.-70℃
参考答案：C
Jane’s dad is getting old, so she has go back home to see him ______ it’s convenient.
A．because
B．whenever
C．although
D．unless
