The correct answer is A) long periods of time without rain.
Desert biomes often have many droughts. The best way to define the underlined word in the sentence above is "A. long periods of time without rain."
Drought means that the region has long periods without rain. Droughts can be caused by lack of rain, high temperatures, overuse of the land, and deforestation. Water supply shortage and crop damages are the most critical consequences of a drought.
