A 58-year-old man with hypertension and benign prostatic hyperplasia (BPH) presents to the clinic. His current medications include lisinopril and finasteride. He complains of persistent urinary hesitancy and weak stream despite 6 months of finasteride therapy. On examination, his blood pressure is 148/92 mmHg. The urologist recommends adding an alpha-1 adrenergic antagonist. Which of the following agents would be the MOST selective for alpha-1A receptors in the prostate, thereby minimizing vasodilation and hypotension?