This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nose and paranasal sinuses, Subject name: ENT
Which of the following is the most common etiological agent is paranasal sinus mycosis? 
Select and explain. 
A. Aspergillus, B. Histoplasma, C. Conidiobolus coronatus, D. Candida albicans
A: Aspergillus
Answer: A: Aspergillus 
Explanation: Paranasal sinus mycoses mean fungal sinusitis. Fungal infections of the paranasal sinuses are uncommon and usually occur in individuals who are immunocompromised. Aspergillus fumigatus is most commonly involved in allergic fungal sinusitis and sinus mycetoma. Many different species are found to involve the paranasal sinuses, the most common being the Aspergillus, Alternaria, Mucor or Rhizopus. (Ref: Textbook of ENT, Diseases of ENT, PL Dhingra, 7th edition, pg no.220)