CORRECT answer is FUNGI. Athlete's foot is caused by the same type of fungus that causes ringworm and jock itch. This can be caused by Damp socks and shoes and warm, humid conditions favor the organisms' growth.It occurs when the tinea fungus grows on the feet. We can catch the fungus through direct contact with an infected person, or by touching surfaces contaminated with the fungus. The fungus thrives in warm, moist environments. They NORMALLY live on the skin, hair, and nails called DERMATOPHYTES. When the environment they live in GETS warm and moist, they grow out of control and start to cause symptoms.