Section B
Directions: In this section, you will hear 3 short passages. At the end of each passage, you will hear some questions. Both the passage and the questions will be spoken only once. After you hear a question, you must choose the best answer from the four choices marked A, B, C and D.
听力原文： Today I would like to continue our discussion of early American agriculture, turning from the raising of crops to the raising of livestock. The animals you would have seen on a typical farm in Massachusetts in the early 1800's would not look quite the same as the ones you might see in the 1980's. In colonial times settlers brought cattle and sheep with them to America from various parts of Europe. Because the settlers were busy building houses, clearing land and planting crops, they had little time to care for their animals. The cattle and sheep had to fend for themselves, and females were bred to whatever bulls and rams who were in the neighborhood. These matings resulted in mixed breeds of cattle and sheep that were hard enough to survive under adverse conditions. As the herds grew, they provided the settlers with meat as well as milk and wool. That was all most 19th century farm families needed: enough food for themselves and a little surplus that could be traded for things they couldn't produce at home. Now the survival of farm animals is not so precarious. Breeding is much more selective and specialized. Purebred cattle and sheep predominate; some bred for their meat, others for their milk or wool.
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A. The differences between sheep and cattle breeding.
B. Food shortages in the early 1800's.
C. Living conditions in the colony of Massachusetts.
D. Livestock raising on early American farms.