This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pharmacology
Carbenicillin : 
Select and explain. 
A. Is effective in pseudomonas infection, B. Has no effect in Proteus infection, C. Is a macrolide antibiotic, D. Is administered orally
A: Is effective in pseudomonas infection
Answer: A: Is effective in pseudomonas infection 
Explanation: None