<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 49-year-old man presents to your clinic with low back pain. When asked to point to the area that bothers him the most, he motions to both his left and right flank. He describes the pain as deep, dull, and aching for the past few months. His pain does not change significantly with movement or lifting heavy objects. He noted dark colored urine this morning. He has a history of hypertension managed with hydrochlorothiazide; however, he avoids seeing the doctor whenever possible. He drinks 3-4 beers on the weekends but does not smoke. His father died of a sudden onset brain bleed, and his mother has diabetes. In clinic, his temperature is 99F 37.2C, blood pressure is 150110 mmHg, pulse is 95min, and respirations are 12min. Bilateral irregular masses are noted on deep palpation of the abdomen. The patient has full range of motion in his back and has no tenderness of the spine or paraspinal muscles. Urine dipstick in clinic is notable for 3 blood. Which chromosome is most likely affected by a mutation in this patient?? A: Chromosome 4, B: Chromosome 6, C: Chromosome 7, D: Chromosome 15, E: Chromosome 16,  <response>: This is a clinical vignette describing a 49-year-old man with flank pain, hypertension, family history of brain aneurysm and diabetes, dark urine, elevated blood pressure, and irregular abdominal masses. The key findings are flank pain, hypertension, family history, dark urine, elevated BP, and abdominal masses. This suggests a diagnosis of polycystic kidney disease, which is caused by mutations in PKD1 on chromosome 16 or PKD2 on chromosome 4. Therefore, the chromosome most likely affected by a mutation in this patient is chromosome 16.E: Chromosome 16 