Which of the following infection involves hair -

Ans. is 'a' i.e., Trichophyton o Dermatophytes are keratinophilic fungi, living only on the superficial dead keratin. That is why they infect skin, hair and nails. In skin they infect the most superficial layer of epidermis i.e., stratum corneum. They do not penetrate living tissues. Dermatophytes cause a variety of clinical conditions, collectively known as dermatophytoses, tinea or ringworm. Dermatophytes have been classified into three genera:- Trichophyton, Microsporum, Epiderm ophyton.o Tricophytons affect - skin, hair and nailo Microsporum affect - skin and hair (nails are not involved)o Epidermophytons - skin and nail (hair not involved)