单项选择题

According to the passage, what was the first great step toward the practice of agriculture

A．The invention of agricultural implements and machinery .
B．The development of a system of names for plants.
C．The discovery of grasses that could be harvested and replanted.
D．The changing diets of early humans.

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热门试题

单项选择题

In Line 15, what is the author's purpose in mentioning a rose, an apple, or an orchid

A．To make the passage more poetic.
B．To cite examples of plants that are attractive.
C．To give botanical examples that all readers will recognize.
D．To illustrate the diversity of botanical life.

单项选择题

According to the passage, why has general knowledge of botany begun to fade

A．People no longer value plants as a useful resource.
B．Botany is not recognized as a special branch of science.
C．Research is unable to keep up with increasing numbers of plants.
D．Direct contact with a variety of plants has decreased.