题目

下列关于中美洲地区早期文明的描述，正确的有( )①已经学会了种植玉米等作物②一些农业聚落逐渐形成③是世界文明最早的发源地④诞生了众多独具特色的文明 A . ①②③ B . ①②④ C . ①③④ D . ②③④ 答案：B .Hearing that a 7.1-magnitude earthquake hit the Yushu county, Qinghai province on April 15,the students’ union______us to donate money for the quake-hit area. A．called up B．called for C．called in D．called on