Ecologist Aldo Leopold Wrote About His Home State of Wisconsin

Ecologist Aldo Leopold wrote about his home state of Wisconsin in The Sand County Almanac. In one moving section, he described a triangular cemetery founded in the nineteenth century that, because of its unusual shape, contained a tiny patch of prairie that was unmowed and undisturbed. Every year, Leopold would watch a single silphium plant bloom there sometime in July. It was the only one he had found in that part of the state. He used this example to discuss the many plants native to the prairie that have been replaced by a few commercial plants grown by farmers. Leopold is observing a change in

A) pollution.
B) suburbanization.
C) social ecology.
D) biodiversity.