Megan+&+Kristen+&+Rachel

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26. When the antibiotic penicillin was first introduced, it was immediately effective in combating staphylococcus bacteria infections. After a number of years, there were outbreaks of staphylococcal infections that did not respond to treatment with penicillin. The best explanation for this situation is that======

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Student could have easily gotten this question wrong because the question was really confusing. First off, I never heard of the phrase 'Antibiotic Penicillin' and 'outbreaks of staphylococcal infections'. I had never read a question like this and thought it was really difficult.======