Your 45-year-old patient has a sore throat. They are afebrile (98.20 F), the pharynx is red, but there is no exudate or cervical lymphadenopathy. They have a runny nose and a mild cough. They are not sexually active. What is the likely infectious etiology of their pharyngitis?

A. beta hemolytic
B. streptococcus
C. Diptheria
D. Adenovirus