Final answer:
The antibiotic that best covers an infection caused by Pseudomonas aeruginosa is Piperacillin, an antipseudomonal penicillin.
Step-by-step explanation:
The antibiotic that best covers an infection caused by Pseudomonas aeruginosa is Piperacillin, which is an antipseudomonal penicillin. Pseudomonas aeruginosa tends to be resistant to most antibiotics, but piperacillin has shown effectiveness against this bacterium. It is important to choose the right antibiotic for treating Pseudomonas infections to ensure successful treatment.