Question

what made the discovery of penicillin significant? it was the first successful use of the compound microscope. it proved germ theory. it helped end the influenza pandemic. it was an effective treatment for bacterial infection.

Explanation:

Penicillin is an antibiotic, which can kill bacteria and is effective in treating bacterial - infections. The compound microscope was in use before penicillin discovery. Germ theory was established before penicillin too. The influenza pandemic was over before penicillin became widely used.

Answer:

It was an effective treatment for bacterial infection.