What type of tube is lighter in color and contains more wood fiber?

The choice of suspension tubes as the correct answer is rooted in their characteristics and function. Suspension tubes, which are produced by certain wood-destroying insects like termites, are designed to transport moisture and food between their colonies and the wood they inhabit. These tubes tend to be lighter in color and contain a greater amount of wood fiber when compared to other tube types.

The composition of suspension tubes facilitates their primary role in supporting the nest structure and enabling the insects to remain hidden from predators while they forage for food. Their lighter color and higher wood fiber content also result from the specific materials termites use in their construction, which typically include fragments of wood and soil.

In contrast, utility tubes serve as pathways for termites to access food sources from a subterranean nest; they are often thicker and darker due to the presence of soil and other materials mixed in as they provide a more robust, protective structure. Exploratory tubes, on the other hand, are often used to scout for potential food supplies and may not have the same structural integrity or composition as suspension tubes. Swarming tubes are specifically related to reproductive activities of the termite colony and are utilized during the swarm season, having a different purpose and construction style.

Therefore, the characteristics of suspension tubes make them distinctive for those