49. The word “arbitrary” in Paragraph 2 is closest in meaning to _______.
(A) based on individual judgment or preference
(B) determined by the rule of the nature
(C) based on common agreement
(D) free from any dogmatic interpretation

45. What is implied but not stated in this essay? (A) Hunters who kill dangerous species are severely punished by law. (B) About a thousand species of animals are in danger of disappearance. (C) The rate of disappearance of mammals is lower now than it was from A.D. 1 to 1800. (D) The growth of the world’s population has meant greater danger to wildlife.

46. What is the main idea of the passage? (A) The processes of physical and mental development are totally different and must not be investigated in the same way. (B) The development of cognitive structures such as language may be influenced by predetermined genetic controls similar to the genetic controls of physical development. (C) For the most part, the structures of language are arbitrary and accidental. (D) The uniformity of speech among individuals in one community supports the social origin of language.

47. According to the passage, what has been true about research into mental processes such as speech development? (A) It has lagged behind research into the development of physical structures. (B) It has benefited from research into the development of physical structures. (C) It has focused on genetic mechanisms. (D) It has assumed strong environmental influence.

48 Which of the following statements is TRUE? (A) Approaches to the inquiry of physical and mental development of human beings have been much the same. (B) It is commonly accepted that the physical structure of the organism is environmentally determined. (C) Human organisms have arms rather than wings because of their learning experience. (D) The physical structure of human organisms is subject to genetic control, although external factors in part influence certain aspects of development.

50. The author says in Paragraph 3 that _________ (A) human cognitive systems have been thoroughly investigated but have proven to be accidental and simple. (B) language is one part of human cognitive structure which is not worth scientific study. (C) the acquisition of human cognitive structure is as miraculous and complicated as the development of physical structure. (D) the study of human cognitive systems is difficult because no scientific evidence is available.

51. Which of the following is UNTRUE about language in the passage? (A) Language is part of the human cognitive structure. (B) Each person acquires a rich and complex language in the process of cognitive development. (C) Individuals in the same speech community need to develop the same language for the sake of communication. (D) The evidence available to the child is fragmentary, so the rich, complex variations of language can make him feel hopeless.

52. How are stupid people similar to smart people? (A) They think alike. (B) Both are very rational. (C) They are physically similar. (D) They are very quiet.

53. According to the author, which characteristic is typical of the ideas of stupid people? (A) Creative (B) Rational (C) Unmemorable (D) Pleasing

54. Why are smart and quiet people not as easy to remember as stupid people? (A) Smart people prefer to remain anonymous. (B) Smart people enjoy being forgotten. (C) The human brain has difficulty in remembering quiet people. (D) Stupid people outnumber smart people.

55. What is the conclusion of this article? (A) Stupid people are always more creative than smart people. (B) Stupidity can be advantageous if it is used smartly. (C) Stupid people do not think. (D) Smart people are worthless.