What defines flame resistant gloves?

Flame resistant gloves are specifically designed to resist ignition and limit burning when exposed to flames or high heat. This characteristic is crucial for protection in environments where there is a risk of fire, such as in firefighting or other industrial settings involving heat sources. The gloves are typically made from materials that have undergone treatments to ensure they can withstand flames for a certain period without catching fire easily or burning away quickly.

While leather can provide some level of flame resistance, it's not a defining characteristic of flame resistant gloves in general. Similarly, being waterproof or lined with cotton does not relate to the gloves' flame resistance. The key factor that identifies these gloves is their ability to not ignite or burn easily, making option B the correct choice.