Choose the word or phrase among A, B, C or D that best fits the blank space in the following passage.
More and more young people are (20) __________ voluntary work abroad. The wild variety of jobs and destinations available is making it an increasingly attractive option for those who have just left school and have a year free before university. Many choose to spend these twelve months working in poor countries. There they will earn little (21) __________ no money. But they will be doing something useful and enjoying the experience.
The work may(22) __________ of helping the local communities, for example by helping to build new road or provide water supplies to isolated rural villages. Other projects may concentrate more on conservation or (23) __________ protection. Whatever kind of job it is, it is certain to be worthwhile, and an experience that will never be forgotten.
More and more young people are (20) __________ voluntary work abroad.