___ that the trade between the two countries reached its highest point．

A．During the 1960s　　　　　 　　　　 B．It was in the 1960s

C．That it was in the 1960s　 　　　　　　 D．It was the 1960s

____________that the trade between the two countries reached its highest point．

      A. During the 1990’s                                              B. That it was in the 1990’s

      C. It was in the 1990’s                                           D. It was the 1990’s