听力原文：W: The law on car is very interesting and I know in London it's different from other places and rules are quite strict, aren't they'?

M: (22)Any London cab driver does a thing called the Knowledge, which is an examination really. It's called the Knowledge and it's a basic test of 468 runs what they call runs from a blue book.

W: Is it difficult to learn the Knowledge?

M: (23)On average, it took me nineteen months. Now it's taking guys three years. It can take anywhere from now to three years. And then you do a driving test at the end.

W: It get the impression they're very strict about taxis. Quite apart from the Knowledge, there's the license. Do you have to get a new license every year?

M: The license is renewed every three years, but your cab, whether you rent it or you own it, has to have a yearly overhaul. I enjoy being a taxi driver and, not only that, it does keep the standard very high, which is what we want in London.

W: (24) Do you feel proud to be a Londoner? Were you born in London?

M: No, I was actually born in Bristol.

W: What do you do in your spare time?

M: Well, (25)I'm into body building. That takes up quite a good deal of my spare time. I might do a system of three days' training with a day off, followed by another three days' training and a day off.

(23)

A．It's composed of 568 runs.

B．It's a blue book.

C．A London driver has to do it.

D．It's an exam.