题目

试管婴儿是（   ） A．只在试管内完成受精作用                       B．胚胎发育的全过程均在体外完成 C．在试管内完成胚胎早期发育                     D．精子和卵细胞是在试管内培养形成的 答案：C问答句匹配________What are those? A It's on the first floor.________Are they hens? B No, they aren't. They're ducks.________Where is the computer room? C They're tomatoes.