What behavior is characteristic of Cat Fleas?

Cat fleas are primarily characterized by their feeding habits, specifically their diet, which consists of the blood of mammals. This feeding behavior is crucial for their survival and reproduction, as they require blood meals to develop from larvae to adult fleas and to produce eggs. When a host mammal is present, cat fleas will quickly find a suitable spot on the animal's body to latch onto and begin feeding.

The other choices do not relate to the behavior of cat fleas. Building nests in wood is common behavior for certain species of animals but not for fleas. Creating silk webs is indicative of arachnids like spiders, which is entirely different from the life cycle and behavior of fleas. Being attracted to light is a behavior observed in some insects, but fleas do not show this attraction; instead, they tend to prefer the warmth and carbon dioxide exhaled by their warm-blooded hosts. This preference is key to their ability to thrive in environments where they can easily find food.