During the early years of the United States environmental movement in the 1960s and 1970s, alarmed activists, warning that nature was in danger of being irredeemably destroyed by human activity, demanded a variety of environmental protections, including the preservation of wilderness areas as national parks. But these environmentalists conceptual framework came under scrutiny shortly thereafter as cultural critics-especially those who were part of the theory revolution that transformed and preoccupied literary study into the end of the century-began to spread the postmodern wisdom that these parks musealized nature and that the wilderness they tried to preserve was not the primeval wild but a social construction. A consensus was growing that all areas of human life-from people's personal attitudes to the mediascapes they inhabited to the ideas they formed and the built worlds in which they dwelt-were socially constructed and these attitudes were quickly extended to nature, especially since ecologists and environmental historians had become so clear in demonstrating the determinative effects on nature of human beings, from ancient to modern times.

One important result of this change in thought was that a number of qualities that 1960s and 70s activist ecologists had felt nature self-evidently possessed seemed to be suddenly undercut and in a startling and provocatively contrarian manner. Most important, natures once apparent otherness seemed suddenly to be no more. In fact, it seemed to vanish in a number of different ways. Human beings had so encroached on nature, the apocalypticisms had shown, that nature was no longer independent of people.Supplementing this sense of radical contemporary change were environmental historians insights into how radically the earths ecosystems had been reshaped over the course of human history,from the emergence of mankind to the invention of agriculture to the rise of modern society. Ideas of a timeless or pure nature were thus discredited. Finally, on the level of intellectual history. nature's “otherness” was undermined in an equally decisive manner when cultural theorists began to argue that this supposed attribute was not only a socially constructed ideology, but an ideology of surprisingly recent vintage. The “otherness” of nature was an ideology that had been put in place during the romantic period of the nineteenth century-and put in place so decisively that it seemed to be the nature of nature.

The passage suggests which of the following about the “conceptual framework”?

It has been misrepresented by certain postmodern thinkers.

It was based on ideas that were rooted in the nineteenth century

It originated with activists eager to protect the natural environment.

It was popularized by theoretical trends that influenced literary studies

It has enjoyed a resurgence since the early years of the environmental movement

Select one answer choice.