21. --- I feel individuals can also cause environmental problems.

--- Yes, do not be _______ about this. Turn lights off if not using them.

  A. particular         B. careful          C. concerned            D. casual

22. Every year for over 100 years, the Nobel Prize _______ to people from around the world for their achievements.

  A. is awarded                         B. has been awarded

  C. was awarded                            D. had been awarded

23. People who cannot _______ between colors are said to be color-blinded.

A. appreciate         B. compare     C. distinguish     D. recognize

24. One reason for her preference for this school is _______, as she put it, it can provide for her future development.

  A. what               B. which            C. that             D. it