Antibiotic resistance is becoming common among organisms that cause a variety of human diseases. All of the following strategies help reduce the risk of antibiotic resistance evolving in a susceptible bacterial population except . a. using antibiotics only when appropriate, for bacterial infections that are not clearing up naturally; b. using the drugs as directed, taking all the antibiotic over the course of days prescribed; c. using more than one antibiotic at a time for difficult-to-treat organisms; d. preventing natural selection by reducing the amount of evolution the organisms can perform; e. reducing the use of antibiotics in non–health-care settings, such as agriculture