单选题心脏形成的关键时期是胎儿期的（）A1～2周B2～4周C3～6周D2～8周E5～10周
单选题
心脏形成的关键时期是胎儿期的（）
A
1～2周
B
2～4周
C
3～6周
D
2～8周
E
5～10周
参考解析
解析：
该题是一道专业知识记忆题。主要考查心脏形成的时期。心脏形成的关键时期是胚胎发育的2～8周，先天性心脏畸形的形成主要在这一时期。该题正确的答案是D。
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