Mark the letter A, B, C, or D to indicate the word that differs from the other three in the position of primary stress in each of the following questions.

1. A. disadvantage                B. communicate          C. traditional            D. presentation
2. A. presentation                  B. conversation          C. responsible           D. explanation
3. A. successful                     B opinion                    C. discussion            D. understand
4. A. contaminate                  B. unfamilar                C. technology           D. electronic
5. A. identify                         B. temperature             C. illegally               D. apology
6. strategy                              B. material                   C. connection          D. advantage
7. A. environment B. presentation C. ecosystem D. respiratory
8. A. awareness B. influence C. pesticide         D. negative
9. A. importance B. expression       C. behaviour D. animal
10. A. habitat B. creative C. protection            D. endangered
11. A. supporter B. researcher C. encourage          D. business
12. A. vehicle B. emission C. pollution          D. depletion
13. A. chemical B. illegal C. disposal D. erosion
14. A. organise B. organic C. introduce D. destruction
15. A. preservation B. unnecessary C. illegally          D. traditional