A、Developmental psychologists. B、Friends of the speakers. C、The same person. D、Fictional characters. C对话中女士提到，His full name is T

M: Hi Helen. What do you think of our class in children’s literature?
W: It looks pretty good. I was surprised to see you in there. Are you also majoring in elementary education?
M: No, I’m not. But as a psychology major, I can use this to fulfill the requirements in developmental psychology.
W: Have you finished the first assignment yet?
M: Not yet. I just got the book today. How about you?
W: I started this afternoon. It’s great fun reading those wonderful children’s stories by Dr. Hughes.
M: Dr. Hughes? I didn’t remember seeing his name on the reading list.
W: His full name is Theodore Hughes Gazzel. That’s how he is listed on the bibliography. Dr. Hughes is his pen name.
M: I love reading those stories as a child. It’s been interesting now to read them from a different perspective. I guess they all give me a good idea on how children think.
W: Those stories are also great for class use.
M: How is that?
W: Well, take a typical Dr. Hughes’ book like The Cat in a Hat. It has a controlled vocabulary of about only 200 words.
M: So, that means the children get a lot of practice, using a small number of words over and over.
W: Exactly. In fact, The Cat in a Hat is written primarily to show how a controlled vocabulary reading could also be interesting and fun.
M: Well, it sounds like it is also going to be interesting and fun. I’ll get started on those readings tonight.
Questions 19 to 22 are based on the conversation you have just heard.
19. What is Helen’s major field of study?
20. Why will the speakers be reading children’s stories?
21. Who are Dr. Hughes and Theodore Gazzel?
22. When does the conversation probably take place?