Câu hỏi 613911 - Tiếng Anh cơ bản 2/Anh văn II - EG09.2

Read the passage and circle the correct choice (A, B, C or D)

Passage 1

In 1881, a new type of weed began spreading across the northern Great Plains. Unlike other weeds, the tumbleweed did not spend its life rooted to the soil; instead, it tumbled and rolled across fields in the wind. The weed had sharp, spiny leaves that could lacerate the flesh of ranchers and horses alike. It exploited the vast area of the plains, thriving in regions too barren to support other plants. With its ability to generate and disseminate numerous seeds quickly, it soon became the scourge of the prairies.

To present-day Americans, the tumbleweed symbolizes the Old West. They read the Zane Grey novels in which tumbleweeds drift across stark western landscapes and see classic western movies in which tumbleweeds share scenes with cowboys and covered wagons. Yet just over a century ago, the tumbleweed was a newcomer. The first sign of the invasion occurred in North and South Dakota in the late 1870s.

Farmers had noticed the sudden appearance of the new, unusual weed. One group of immigrants, however, did not find the weed at all unfamiliar. The tumbleweed, it turns out, was a native of southern Russia, where it was known as Tartar thistle. It was imported to the United States by unknown means.

Frontier settlers gave the plants various names: saltwort, Russian cactus, and wind witch. But botanists at the Department of Agriculture preferred the designation Russian thistle as the plant’s common name. However, these botanists had a much harder time agreeing on the plant’s scientific name. In general, botanists compare a plant to published accounts of similar plants, or to samples kept as specimens. Unfortunately, no book described the weed and no samples existed in herbaria in the United States.

     From the passage it can be inferred that the botanists at the Department of Agriculture