A、On weekend. B、On Sunday. C、On workday. D、On Saturday. B

Robinson: Li, I suggest we do a quick tour of central London. As it is Sunday, there is very little traffic. What do you think?
Li:   That’s a great idea, Ro.binson. What a wonderful view!
Robinson: It is, isn’t it? We are now on the south bank of the Thames. You can see the Houses of Parliament and Big Ben from here. I used to work as a tourist guide when I was a student. Let’ s see if I can still do it. We’ re now crossing Lambeth Bridge into Westminster. Now we can turn right and drive past Wesuninster Abbey, where the kings and queens of England are crowned.
Ll:  What’s that park on the left?
Robinson: That’s St. James’s Park. We’ll drive back here later. Now we’ re going along Whitehall. Number 10 Downing Street, where the Prime Minister lives, is on your left.
Ll:   Is that the one with the policeman standing outside?
Robinson: That’s it. We’re coming into Trafalgar Square. This is equally famous for its statue of Horatio Nelson and its pigeons.
Ll:  Horatio ... ?
Robinson: Nelson. The naval captain who defeated Napoleon at the battle of Trafalgar in 1805, and so stopped him from invading England. And this is Piccadilly Circus with its statue of the Greek god of love, Eros. This area we are coming into now is called Soho. This is London’s Chinatown.
Li:   Now I know where m come when I feel homesick!
Robinson: I hope you’re not feeling homesick already. This area is the main entertainment district. You’ll find most of the cinemas and theatres here. We’re now going up Chafing Cross Rd., and on your left is the world’ s biggest bookshop Foyles.
Li:   Do they sell science books?
Robinson: They sell books on every subject and in most languages. Now we’ll drive around the British Museum so that you can get your bearings.
Li:   Isn’t this where Marx used to collect material for Capital?
Robinson: That’s right. He used to work in the British Museum Reading Room. You’ll be working there too shortly. The University of London is only a few minutes walk from here. This is Oxford St. the main shopping district. Every British department store has a branch here.
Li:   It’s very quiet for a shopping centre.
Robinson: That’s because it’s Sunday. All the big shops are closed. The rest of the week it’s crowded with tourists. Here we are at Marble Arch, at the northeast corner of Hyde Park.
Li:   What are all those people over there shouting about?
Robinson: That’s Speaker’s Comer. E. very Sunday people come here to argue about every subject under the sun from how the Earth is really flat to the danger of nuclear war.
Lt:   I must come here one Sunday.
Robinson: As a speaker or a heckler?
LI:   Neither. As a spectator only!
Robinson: Now where driving down Park Lane. On the left is Mayfair — the embassy quarter.
LI:   Where is the Chinese Embassy?
Robinson: It’s not here. It’s in Portland Place, just south of Regent’s Park.
Li: Is that Hyde Park on the right?
Robinson: It certainly is. And we’re coming into Green Park now. We’ll have a quick look at Buckingham Palace. Every morning at exactly 11:30, from April until the end of September, the Changing of the Guard takes place.
Li:   So, that’s the palace! By the way, is our College far from here?
Robinson: No, only about ten minutes. Now, we’ re coming into your neighbourhood.