What does the word "they” in the fourth paragraph refer to?

I don't think we should _________ a decision yet; we should wait until everything is examined.

You should make an __________ with your doctor whenever you have a health concern.

I ________ dinner with my family when she phoned.

He _________ a second clear foul and was sent off.

Read the following passage and mark the letter A, B, C, or D on your answer sheet to choose the word or phrase that best fits each of the numbered blanks from 26 to 30. 

     Although education in Singapore is free, all families must pay small ‘miscellaneous' fees, (26) _______ are explained by the Ministry of Education. These fees are fairly small for public schools but don't necessarily cover additional costs for things like uniforms, transport, and school materials. Independent schools, even if part government-funded, can (27) _______ fees beyond the small amounts seen in the public school system. If you do not choose the state system and decide to find a fully private or international school, the costs are higher. 

     Singapore has a huge range of international schools, teaching in English and (28) _______ major world languages. Schools might use the International Baccalaureate syllabus, or a (29) ________ of another national curriculum such as the American core or Australian standard curriculum. International schools are generally of a high standard, and (30) ________ typically competitive, with testing and interviews to secure admission. You can expect the fees to vary widely depending on the specific school and the program they offer. Fees of anything from USD 15,000 to USD 30,000 a year aren't uncommon, with extras such as registration fees and deposits. 

When I came home last Sunday evening, my parents prepare for the meal.

After three years of _______ the country's economy is finally looking a lot healthier.

__________, I will have worked at this school for 30 years.