A nurse is providing teaching to an older adult client about factors that increase the risk of urinary tract infection. Which of the following information should the nurse include?

A. "Bladder capacity decreases in older adults." While bladder capacity does decrease with age, this alone does not directly increase UTI risk. B. "The urethral sphincter functions less efficiently." Although sphincter function may decline, this typically leads to incontinence rather than urinary retention, which is the main UTI risk factor. C. "Decreased bladder tone can cause urinary retention." Urinary retention leads to stasis of urine, promoting bacterial growth and increasing UTI risk. D. "The ability to concentrate urine decreases." Decreased ability to concentrate urine does not directly cause UTIs, though it may lead to dehydration, which could contribute to UTI risk indirectly.