Final answer:
If Mr. John has symptoms of productive cough, fever, and infiltrate on his chest X-ray, an appropriate medication choice would be Vancomycin + Pip/Tazo.
Step-by-step explanation:
If Mr. John returns in 2 weeks' time with symptoms of productive cough, fever, and infiltrate on his chest X-ray, he may have a bacterial infection. Given the information provided, an appropriate medication choice would be A. Vancomycin + Pip/Tazo. This combination is effective against many gram-negative bacteria commonly associated with pneumonia, such as Pseudomonas aeruginosa and Klebsiella pneumoniae.