Read the following passage and choose the best answer A, B, C or D. 36. What is the main topic of the passage? * A. Scientists searching the Amazon River Basin B. The weight of anaconda snakes C. The green anaconda’s rive life D. Finding and studying large green anacondas 37. The word “they” in the first paragraph refers to______. * A. native people B. snakes C. scientists D. Europeans 38. According to the passage, all of the following can be threats in the Amazon River Basin except_____. * A. native people B. local disease C. lack of roads D. dangerous animals 39. The word “poisonous” is closest in meaning to ______. * A. heavy B. hungry C. harmful D. long 40. Which of the following is true about the Amazon River Basin? * A. It is home to yellow anacondas B. It often rains and floods. C. It is highly unexplored. D. It is relatively more developed.