What might indicate an active termite presence in a structure?

Swarming insects near light fixtures is a strong indicator of active termite presence, particularly for certain species such as subterranean termites and drywood termites. When conditions become favorable, usually during warm months or after rain, winged reproductive termites, also known as alates, may leave their colony in search of a mate and to establish new colonies. This swarming behavior often occurs near light sources, which can mistakenly attract the insects.

While the other choices may suggest issues related to structural stability or moisture problems, they are not as direct as the presence of swarming insects. For example, dry wood in columns may suggest a past infestation but does not confirm current activity. Severe cracks in the foundation highlight potential structural weaknesses but do not directly indicate termite damage. Peeling paint on walls can result from moisture infiltration or other issues and is not an exclusive sign of termites. Therefore, swarming insects are the most telling sign of an active infestation, providing a clear indication that termites are currently present and posing a risk to the structure.