What is said about the research paper a. The paper came out as short as I expected. b. Actually the paper was long enough to cover it. c. The paper was short enough to present. d. The paper turned out better than I had expected.

《国家电网公司2011年新建变电站设计补充规定》要求，站控层交换机宜采用（）电口，220kV及以上电压等级变电站站控层交换机之间的级联端口宜采用1000M端口。