单选题 Revolutionary developments in China's astronomy took place in the 1960's.
  • A. commenced
  • B. occurred
  • C. were disputed
  • D. were exchanged


【正确答案】 B
【答案解析】take place和occur同义：发生、出现；commence：开始、着手；were disputed：被讨论、被争论；were exchanged：被交流、被交换。