Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks from 19 to 24.

When travelling, hostels are usually the cheapest places to stay. They (19) ______ five to thirty dollars a night. The 7,000 youth hostels around the world vary greatly: some are beautiful and comfortable, but others are not! All of them, however, are usually ' clean and safe. Hostels are always full (20) ______ other people travelling cheaply, (21) ______ they are good places to meet people and exchange information. There are usually ten or more beds in a room. Women and men sleep (22) ______. In hostels, each visitor must bring his or her own sleeping bag and towel. (23) ______ hostels also require you (24) ______ the hostel during the day.