Which of the following methods does NOT result in bacterial attenuation?

Show Answers

Cultivating bacteria under stressful conditionsPropagating bacteria in a non-native hostContinuous passage through a laboratory animal modelRepeatedly growing bacteria in synthetic culture media

Explanation

Attenuation can be produced by growing bacteria in harsh environments, using unusual hosts, or by repeated culturing in artificial media. However, serial passage through an experimental host typically maintains or enhances virulence rather than causing attenuation.