She _____ some sugar, flour and butter to make somecookies.       [ ]

A. combined                        

B. connected      

C. joined                                

D. united

卖主先出低价来引起买主的兴趣，再假装发现一个错误，撤回低价，这属于()方法。

A．错误试探

B．仲裁试探

C．替代试探

D．开价试探