Deserts Typically Occur in a Band Around 30 Degrees North

Multiple Choice

Deserts typically occur in a band around 30 degrees north and 30 degrees south latitude because

A) descending air masses originating from the tropics tend to be dry.
B) trade winds have little moisture.
C) moisture-laden air is heavier than dry air and is not carried to these latitudes.
D) these locations get the most intense solar radiation of any location on Earth.