Otomycosis is most commonly caused by-

Ans. 'a' i.e., Aspergillus Otomycosis* Otomycosis, also called acute fungal otitis externa, describes a fungal or yeast infection of the external auditory meatus.* Aspergillus niger accounts for 90% of otomycosis infections.* Other common organisms are Candida albicans (2nd most common) and Aspergillus fumigatus. Less common organisms are Phycomycetes, Rhizopus, Actinomyces and Penicillium.* Saprophytic fungi potentially residing in the ear canal include Aspergillus, Candida albicans, Phycomycetes, Rhizopus, Actinomyces, and Penicillium.* Under certain conditions of increased heat, humidity, glucose concentration (diabetes), immunosuppression, or overuse of systemic or topical antibiotics and steroids, these saprophytic fungi can become pathogenic.