Which of the following is a common use for doxazosin in the treatment of benign prostatic hyperplasia (BPH)?

A. To reduce the size of the prostate gland: Doxazosin does not reduce the size of the prostate; it works by relaxing smooth muscle to improve urinary flow. B. To increase testosterone levels: Doxazosin does not affect testosterone levels; it is an alpha-blocker that helps with urinary symptoms of BPH. C. To treat urinary tract infections: Doxazosin is not used for treating infections; it addresses symptoms related to BPH. D. To relax the smooth muscles in the bladder neck and prostate: This is correct. Doxazosin is an alpha-1 adrenergic blocker that helps relax smooth muscles in the prostate and bladder neck, improving urine flow and relieving symptoms of BPH.