Final answer:
Antibiotics do not kill fungi like Candida albicans, which causes yeast infections. Disruption of the bacterial balance in the body can allow Candida to overgrow and cause a secondary yeast infection.
Step-by-step explanation:
Antibiotics are prescribed for urinary tract infections (UTIs) to kill the bacteria causing the infection. However, antibiotics do not kill all types of microorganisms, including fungi like Candida albicans, which causes yeast infections. The antibiotics prescribed for the UTI will only target the bacteria and may disrupt the balance of bacteria in the body, allowing opportunistic fungi like Candida to overgrow and cause a secondary yeast infection.