Which of the following is a common method used to control bat intrusions?

Naphthalene is often used as a repellent due to its strong odor, which many animals, including bats, find unpleasant. This method exploits bats' keen sense of smell, making the environment less hospitable for them. It's used primarily as a deterrent to encourage bats to leave an area without causing them harm.

While trapping is also a method that can be employed to control bat populations, it is more invasive and can be less effective for nuisance situations since it does not prevent future intrusions. Heavy illumination might deter bats to some extent, but it can disrupt other wildlife and is not a long-term solution. Encouraging predator presence is generally ineffective in controlling bat populations because bats are aerial and often evade ground predators. Thus, using naphthalene is recognized for its effectiveness in creating an unwelcoming environment for bats.