右图为某家族关于白化病的系谱图，问Ⅱ3和Ⅱ5都是纯合体的几率为（）。
A、l/4
B、1/3
C、1/6
D、1/9
参考答案：D
请结合上下文将下列对话补充完整。
1. — What's he doing now?
— He's __________________ football.
2. — When do you go to school?
— I often __________________ to school at 7: 30.
3. — What's Lily doing now?
— She is __________________ chess with Mike.
4. — Do you like counting insects?
— No, I __________________. I __________________ collecting leaves.
5. — Is she writing a report?
— No, she __________________. She is __________________ a picnic.
诊断消化性溃疡首选（）
A.钡剂造影
B.胃镜检查
C.胃液分析
D.腹部B超
E.腹部CT
