问题
                    
8 We missed our train, and ___ the next train was delayed, ____ we had to wait for two hours
                            A:on top of that; in that case
B:as a result; so that
C:because; therefore
D:what was worse; in which case
                        
                        B:as a result; so that
C:because; therefore
D:what was worse; in which case
正确答案是:
                        