Which of the following would be classified as a biological hazardous material?

The classification of biological hazardous materials is based on the potential for harm posed by living organisms or their byproducts to human health and the environment. Virus samples fit this definition because they are pathogens that can cause diseases in humans, animals, or plants. Handling virus samples requires certain safety protocols to mitigate the risk of infection or spread.

In contrast, mercury is considered a heavy metal and poses a chemical hazard due to its toxicity and environmental impact. Gasoline, a flammable liquid, presents fire and explosion hazards, while asbestos is a mineral fiber linked to respiratory diseases and environmental concerns, but neither of these materials is classified as biological. Thus, virus samples are the only option that directly involves biological hazards, making it the correct choice.