The larval stage of members of class Monogenea is called the ( ). A: redia B: oncosphere C: sporocyst D: oncomiracidium E: cercaria

血吸虫生活史中的第一个幼虫时期是 ( )。 A: 雷蚴 (redia) B: 毛蚴 (miracidium) C: 尾蚴 (cercaria) D: 胞蚴 (sporocyst) E: 囊毛蚴 (oncomiracidium)