<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 53-year-old female visits her physician with watery diarrhea and episodic flushing. The patient reports that she is often short of breath, and a pulmonary exam reveals bilateral wheezing. A CT scan shows a mass in the terminal ileum. 24-hour urine collection shows abnormally elevated 5-hydroxyindoleacetic acid HIAA levels. Ultrasound demonstrates a tricuspid valve with signs of fibrosis with a normal mitral valve. A metastatic disease to which organ is most commonly associated with the patients syndrome?? A: Lung, B: Kidney, C: Brain, D: Liver, E: Pancreas,  <response>: This is a clinical vignette describing a patient with symptoms of watery diarrhea, flushing episodes, shortness of breath, wheezing, and a mass in the terminal ileum. The key findings are elevated 24-hour urine 5-HIAA levels and tricuspid valve fibrosis. 5-HIAA is a metabolite of serotonin, and elevated levels can indicate a serotonin-producing tumor. Tricuspid valve fibrosis suggests right-sided heart involvement. Together, these findings are classic for carcinoid syndrome caused by a serotonin-secreting carcinoid tumor. The question asks which metastatic site is most commonly associated with this syndrome. D: Liver 