This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pharmacology
which of the following antimicrobials should not be given to a 4C asthmatic patient managed on theophylline therapy ? 
Select and explain. 
A. ERYTHROMYCIN, B. CEFOTIXIME, C. COTRIMOXAZOLE, D. AMOXICILLIN
A: ERYTHROMYCIN
Answer: A: ERYTHROMYCIN 
Explanation: THEOPHYLLIN + ERYTHROMYCIN = QT PROLONGATION REF : KD TRIPATHI 8TH ED