Question

in addition to gaining or losing thermal energy, air in an air mass can gain or lose water vapor as it remains over a source region. in certain source regions, large amounts of water evaporate from earths surface into the lower atmosphere. air masses that form over these source regions can gain water vapor. as air gains water vapor, the humidity of the air increases.
the map below shows two air mass source regions, labeled a and b. the colors on the map show average evaporation.
data source: cort j. willmott and matsuura kenji, terrestrial water budget data archive: monthly time series (1950 - 1999), 2001.
click the blue words to correct the statement below.
less evaporation occurred in region b than in region a. compared to the air above region a, the air above region b gained more water vapor from earths surface. so, an air mass that formed over region b would have been less humid than an air mass that formed over region a.

Explanation:

The text states that more evaporation occurs in Region B compared to Region A. Since more evaporation means more water - vapor is added to the air from Earth's surface, an air - mass forming over Region B would have higher humidity. The original statement has incorrect information about evaporation amounts and resulting humidity.

Answer:

More evaporation occurred in Region B than in Region A. Compared to the air above Region A, the air above Region B gained more water vapor from Earth's surface. So, an air mass that formed over Region B would have been more humid than an air mass that formed over Region A.