Question 21. A. legal        B. diverse                      C. polite                        D. complete

Question 20:         A. comprise           B. combat              C. convert              D. conceal

Question 19:         A. geographical     B. environmental   C. agricultural        D. biological

Question 18:         A. postpone           B. specialize          C. purpose             D. summarize

Question 17:         A. ability                B. sympathetic       C. political             D. significant

Question 16:         A. pleasure             B. capture              C. picture               D. ensure

Question 15:         A. particular           B. circumstances      C. environment     D. advertisement

Question 14:         A. diversity            B. disastrous          C. circulate            D. alternative

Question 13:         A. cultural              B. priority              C. advantage          D. occurrence

Question 12:         A. endanger           B. geometry           C. opposite            D. geography