【Yoho】評論
The origin of complex organisms (called eukaryotes) ( - which includes all animals, plants, and fungi-) _____ one of biology’s biggest mysteries.主詞( ) 補充說明，可省略_____ 主要動詞 (不會莫名其妙變化成being和been，所以先去掉選項C、D) 主詞補語The origin of complex organisms called eukaryotes- which includes all animals, plants, and fungi- _____ one of biology’s biggest mysteries.