单项选择题
A．When a pottery piece from any batch was broken during finishing, Stone Age people sometimes deliberately smashed the rest of that batch, perhaps to avert bad luck.
B．The composition of clay, which affects the durability of any pottery made from it, varies greatly from one area of the world to another.
C．Pottery was invented in the Stone Age, and techniques for making pottery were mastered well before those required for delicate ceramic work.
D．Stone Age potters drafted pottery figurines as frequently as they did ceramic pieces.
E．Many Stone Age rituals involved the destruction of a pottery figurine, perhaps as a sacrifice to the gods.
单项选择题 Currently, the number of first-time admissions of individuals diagnosed as manic-depressives to hospitals in Great Britain exceeds by nine times the number of admissions of such patients to public and private hospitals in the United States, even though the population size of the United States is many times that of Great Britain. Which of the following, if true, would be most useful to an attempt to explain the situation described above ？（）
单项选择题 A new ordinance passed by the Gorenton Council a year ago banned the sale of all nonrecyclable plastic packaging for food being sold in Gorenton. A substantial percentage of Gorenton’s plastic waste, however, is still composed of nonrecyclable plastic food packaging. Which of the following, if true, best contributes to reconciling the apparent discrepancy above ？（）
单项选择题 Extinction is a process that can depend on a variety of ecological, geographical, and physiological variables. These variables affect different species of organisms in different ways, and should, therefore, yield a random pattern of extinction. However, the fossil record shows that extinction occurs in a surprisingly definite pattern, with many species vanishing at the same time. Which of the following, if true, forms the best basis for at lest a partial explanation of the patterned extinction revealed by the fossil record ？（）