What is used to fill gaps in seams between unibody components to prevent air and moisture from entering?

The correct answer is sealers, which are specifically designed to fill gaps in seams between unibody components. They serve to prevent air and moisture from penetrating and causing rust or structural issues in the vehicle. Sealers can create a waterproof barrier, ensuring that the internal structures are protected from environmental factors.

Sealants, while similar, typically focus on adhering surfaces together and may not always be as effective in preventing moisture intrusion in the way that sealers are. Fillers are primarily used to repair surface imperfections and may not provide the same level of protection against air and moisture as sealers do. Adhesives are meant for bonding materials together and might not have the necessary properties to effectively seal gaps against moisture and air intrusion.

Understanding the distinction between these terms is crucial for anyone involved in auto body repairs, as it impacts the longevity and safety of the vehicle's structure.