A、The bad manners of cell phone users. B、The damage to users’ ears. C、Too much use on little things. D、Bad effect on others’ ear

M: I was just reading this article about the wonders of the ancient world. A lot of them were buildings. I was thinking, what would your wonders of the modern would be? Not necessarily buildings, but things that have changed our way of life.
W: For me, well, I was thinking the cell phone is the most wonderful thing.
M: Really?
W: Yeah, (19) I even couldn’t live without mine. It’s so convenient! I can call my friends anytime and they can always call me. Or if I’m in trouble I can call for help...
M: You mean like calling your parents?
W: Yeah, like parents, and if I’m running late, I’m able to call a friend if I’m, like, on the bus or something.
M: (20) But the problem with cell phones is that people use them too much for every little thing. It’s practically glued to their ears.
W: Yeah, and I hate it when people shout into them in a public place and everyone else has to listen to the conversation, especially in restaurants.
M: Well, good manners aren’t a wonder of our world! You know, I think the most amazing wonder is e-mail. It has changed the world, and it has totally transformed my business. Everybody at work is always on the computer, responding to e-mails, sending e-mails... That’s where most of our business is done now, through e-mail. You are sending reports, getting information. But the bad part is that you are glued to the computer and people expect things to be done right away.
W: Yeah, people are shocked if you go through a day without checking your e-mail. And when you go on vacation and then you come back, maybe there are 200 e-mails waiting for you — all of them urgent.
M: I guess it is like any other tool or device. (21) If it’s used correctly, it’s very useful.
19．Wily does the woman consider the cell phone one of the wonders of the modem world?
20.What is the problem with cell phones according to the man?
21.How does the man feel about e-mail?