Which mosquito species is known to feed on farm animals in addition to humans?

The correct answer is Aedes vexans. This species is known to have a broad diet that includes not only humans but also farm animals such as cattle, horses, and pigs. Aedes vexans is a generalist feeder, making it more adaptable in various environments where farm animals are present.

In contrast, the other species listed have more specific feeding behaviors. Anopheles quadrimaculatus primarily feeds on humans and is notable for its role in malaria transmission, but it does not typically feed on farm animals. Aedes triseriatus and Aedes canadensis are more specialized in their feeding habits, primarily relying on humans and/or certain wildlife, but they do not commonly feed on livestock. Therefore, Aedes vexans stands out for its ability to feed on a wide range of hosts, including both humans and farm animals.