Which type of hazard could a biohazard symbol indicate?

The biohazard symbol specifically denotes the presence of biological agents that pose a risk to human health, such as infectious materials. This symbol is commonly found in laboratories, medical facilities, and areas where biological research is conducted, indicating that the materials present could potentially cause disease or infection.

Understanding the context of the other hazards is crucial. Chemical burns are related to exposure to harmful chemicals, and while they can be serious, they wouldn’t typically be indicated by a biohazard symbol. Reactive substances involve chemicals that can react dangerously under certain conditions, and explosives pertain to materials that can explode, which are unrelated to biological hazards. The biohazard symbol focuses specifically on risks associated with biological agents, making infectious materials the appropriate answer in this context.