选A,B是赔偿的意思,原句是谁来买单/谁付帐的意思,固定搭配pay the bill.
pay
[pei]
n.
薪水,工资
v.
支付,交纳,给予,有利,值得,合算
pay for
v.
偿还,赔偿
pay off
v.
还清(债务等)付清,报复,赢利
pay out
v.
付出,报复