In the gutters under the eaves and between the shingles of the roofs, a white granular powder still showed a few patches; some weeks before it had fallen like snow upon the roofs and the lawns, the fields and streams.

Which best explains how the phrase “white granular powder” supports the author’s purpose of calling attention to the environment?

The powder is an unnatural substance.
The powder has a texture like sugar.
The powder looks like freshly fallen snow.
The powder is used in house construction