情景对话（每题1分，共5分）请将正确答案序号填到题号前，有两项为多余选项。

小题1:—I am sorry, I couldn’t find the book you want to borrow.

—________

小题2: —How was your visit to Lake Tai？

—______

小题3:—Professor Wang, I haven’t finished my paper.

—_____. You have some time left.

小题4:- The car looks nice. Could I have a try before I decide to buy it?

　- _____________

小题5:—Would you like another piece of cake?

—___________. I’m still hungry.

小麦高秆（H）对矮秆（h）是显性。现有两株高秆小麦，它们的亲本中都有一株矮秆小麦，这两株小麦杂交，在F1中出现纯合子的概率是（）

A.75%

B.50%

C.25%

D.12.5%