根据对话情景选择恰当的选项，其中有两项是多余的。

Jeff: What’s wrong with Miss Wang? 小题1:  

Tim:   小题2: She went to the theater three times this week, but every time she failed to get the ticket. I think she really wants to see it.

Alex: I hope she can see the movie next week. It’s my favorite movie, too. 小题3: 

Betty: I prefer Avatar 3D. It’s so colorful and interesting. Jeff, do you like Beijing Opera?

Jeff:   小题4:  But some of my friends like it a lot. It’s full of famous stories and beautiful facial paintings.

Alex:   小题5: 

Jeff:  I like Tom and Jerry best. It’s so funny.

半数有效量是

A．产生最大效应所需剂量的一半

B．引起50%阳性反应（质反应）或50%最大效应（量反应）的浓度或剂量

C．一半动物产生毒性反应的剂量

D．产生等效反应剂量的一半

E．用治疗量的一半