A child presents to his physician with fever, a nonproductive cough, and shortness of breath. The physician orders a routine sputum culture and an acid-fast bacillus culture and smear. The smear shows red organisms arranged in ropes. What is the most probable cause of this child's fever and cough?
A) Mycobacterium leprae B) M. avium C) M. intracellulare D) M. tuberculosis