21. At the time of the Mexican agrarian revolution, the most radical faction, that of Zapata and his followers, proposed a return to communal ownership of land, to what had been a pre-Columbian form of ownership respected by the Spaniards. (A) land, to what had been a pre-Columbian form of ownership respected by the Spaniards (B) land, a form of ownership of the pre-Columbians and respected by the Spaniards (C) land, respected by the Spaniards and a pre-Columbian form of ownership (D) land in which a pre-Columbian form of ownership was respected by the Spaniards (E) land that had been a pre-Columbian form of ownership respected by the Spaniards 为什么选A呢