A 25 years old female complains of recurrent rhinitis, nasal discharge and bilateral nasal blockage since one year. She has history of asthma and allergy. On examination multiple ethmoidal polyps are noted with mucosal thickening and impacted secretions in both the nasal cavities. Biopsy is taken and the material is cultured which shown the growth of many hyphae and pseudohyphae with dichotomous branching typically at 45deg. Which of the following is the most likely responsible organism?