listening:02-10-45

45. In the earlier 20th century, what did train travelers do when they got thirsty?

. (A) They drank from public water fountains.

(B) They passed around a cup of water.

(C) They drank from personal tin cups that they carried with them.

(D) They bought a paper cup of water.

The answering key is B, I think that it is C, can anyone tell me which one is correct? Why it is B?

Thanks so much.