Here are the correct answers for each question based on the context provided:

1. A. have
2. C. which
3. C. happens
4. A. assignment
5. C. order
6. B. looking out
7. D. being mended
8. B. have
9. C. build
10. D. built
11. A. bring
12. B. theory
13. A. good time
14. C. chance
15. B. signatory
16. A. mechanic
17. B. teaching
18. C. shines
19. C. preference
20. D. explanation

Total: 20 questions

Let me know if you need anything else!