The phrase best describes the danger the sandstorm represents to the travelers, "the sun and sky quickly retreated".
A dust storm, often known as a sandstorm, is a weather phenomenon that occurs frequently in dry and semi-arid areas.
Dust storms form when a strong wind, such as a gust front, pushes sand and dirt from a dry surface.
The primary terrestrial sources of airborne dust are drylands in the Arabian Peninsula and North Africa.
Thus, the correct option is C. "the sun and sky quickly retreated"
Learn more about the sandstorm
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