A、Because he wants to smoke. B、Because it’s a gift for his son. C、Because he collects lighters. D、Because he forgets to take it

W: Excuse me. Do you have any keys or cellphones in your pockets?
M: No. No. I think I’ve taken everything out.
W: Okay. Go ahead and walk through the body scanner.
M: Will I feel anything? Is it safe?
W: No sir. You won’t feel anything. It is safe of course. Just walk through and keep your hands in the air.
M: Okay.
W: Sorry, sir. The scanner indicates that we need to do some additional screening. Please come this way.
M: What? Did I... Did you find something?
W: Relax sir. Okay? I’m going to open your carry-on bag. As I’m going through it, please do not try to touch it.
M: Okay.
W: Let’s see now. Hmmm. First of all, sir, [6]you can’t take any liquids like this bottled water past this point. It is not allowed.
M: Ah. I just bought it before I got in. Thirsty, you know. And it’s just water. Not anything dangerous.
W: Sorry. That’s the rule. And, sir. What’s this?
M: What?
W: No, sir, you cannot bring a lighter on the plane. Don’t you know that?
M: Well, but I don’t smoke. I mean, [7]I just bought it for my son. He collects lighters. I won’t use it on the plane. It’s okay, right?
W: [8]You still can’t bring it on the plane. It’s the rule. I’m sorry that you have to leave it here.
M: Why? I promise I won’t use it on the plane. I promise...
W: I’m sorry, but I have it just in case of emergencies. You know, as an emergency fire starter in case the plane crashes into a dark forest. Ah, what’s this?
M: Well... That’s my pocket knife.
W: A pocket knife? It’s almost a foot long!
M: [9]Well, it’s a special knife given to me by my grandfather, but I only use it to peel apples and fruit. You know... Things like that.
W: Sir. I’m sorry, but you can’t take that on the plane. In fact, do you have any other prohibited items in your bag? I mean, didn’t you read the sign back there explaining all of the items that were not allowed on board?
M: Well, I started to read it, and I then got a little distracted.
W: A little? Sir. [10]How many times have you flown on an airplane?
M: Uh, it has been a while. I think the last time I traveled by plane was about, uh, 1990... I know it’s been a long time. I just haven’t the chance to go far away. And this time...
W: Sorry, sir. Why don’t you come with me?
M: What?
W: I think my supervisor would like to ask you a few questions.
M: Oh, no!
6．What kind of liquids does the man bring with him?
7．Why does the man bring a lighter in his carry-on bag?
8．Why should the man leave the lighter there?
9．What does the man use the pocket knife for?
10．Where does the conversation most probably take place?