Answer:
(B) heated air in an uninsulated, unvented attic.
Explanation:
-Ice dams are formed by an interaction between snow cover, outside temperatures, and heat lost through the roof – more specifically, from heat loss through the poorly insulated ceiling of the house into the attic area and under the roof.
-Hot, humid air trapped in attics can also cause moisture to accumulate, resulting in mold or mildew.