was the first(B) American woman to have earn(C) the Ph.D. degree(D).

18. The changes that occur(A) in the life cycle(B) of a butterfly or moth are probable(C) the most striking examples(D) of metamorphosis.

19. In the nineteenth century, North American locomotives ran(A) on hardwood fuel(B),Which was inexpensive(D) and plentiful in the time.

20. Much(A) theories have been(B) developed concerning how(C) people learn about cultures from the myths and legends passed down from one generation to   another(D).

21. Several comet(A) are discovered each year, but very few of them(B) are bright(C) enough to be seen(D) without the aid or magnification.

22. Charles Monroe Schulz's comic(A) strip "Peanuts" is translated into(B) 26 languages also(C) has appeared in over 2,300 daily(D) newspapers.

23. In human beings the liver is(A) the biggest(B) glandular organ(C) of his(D) digestive system.

24. Many scientists(A) contributed to(B) the development of(C) television, whether(D) no one person can be said to have invented it.

25. Northern Canada contains(A) vast areas treeless(B) of low(C) vegetation known(D) as tundra.

26. Gordon Parks composed wrote(A), and directed Martin, the(B) classical ballet who(C)Examines the meaning of the life of(D) Martin Luther King. Jr.

27. In 1965 Rodolfo Gonzales has estab1ished(A) an organization(B) called(C) the Crusade For Justice in(D)  Denver, Colorado.

28. Large, heavy(A) draft horses were commonly(B) used for labor farm(C) in the United States before the(D)  introduction of tractors.

29.Herads of migrating caribou, members(A) of the deer family arc an important(B) economically(C) resource to Inuits and other Native Americans.

30. Some(A) nineteenth-century advocates(B) for the emancipation of women in the United States were also activity(C) in the Underground Railroad, helping(D) slaves to  escape.

31. Feathers not only(A) protect birds from injury and conserve(B) body heat but also function in flight(C). courtship, camouflage, and sensory perceptive(D).

32. The radio telescope, invented(A) in 1932, has capabilities(B) beyond far(C) those ofoptical telescopes in tracking(D) signals from galaxies.

33. Rafting was an(A) essential mean(B) of transportation(C) from prehistoric times(D) to thenineteenth century.

34. Many fortification(A) rank among the most(B) functional and beautiful works of(C)architecture constructed(D) in North America before the twentieth century.

35. Because(A) her work was popular with(B) European royally, Harriet Goodhue Hosmer became financial(C) successful as a sculptor in the(D) mid-eighteen hundreds.　

36. The actor(A) James Earl Jones gained(B) Broadway stardom in "The Great Whitehope" for his powerful(C) portrayal of prizefighter(D).

37. Despite(A) fats and oils arc nutritionally(B) important as(C) energy sources, medical research indicates(D) that saturated fats may contribute to hardening of the arteries.

38. Large multicolored insects with(A) four wings, dragonflies play(B) a very important role in the ecosystem of humid