The correct option is A Fungi
Ringworm is a fungal skin infection. It is not due to a worm as its name implies. There are many types of fungal germs (fungi) that can infect the skin, nails and hair. Fungal infections are also known as tinea or dermatophyte infections or dermatophytosis. Ringworm is contagious and can be passed from person to person by contact with infected skin areas or by sharing combs and brushes, other personal care items or clothing.