A US coal producer agreed to pay ________ total of $ 209 million for the mining accident that killed 29 people，________ worst such disaster in 40 years in the US.

A．the；the

B．a；a

C．the；a

D．a；the

提问客户感兴趣、容易回答或邮政速递业务能够解决的状况性问题，其目的是为了拉近双方的距离，并快速消除陌生感。