<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 10-year-old boy is brought by his mother to his pediatrician for skin growths. His mother reports that she started noticing small lumps arising from the patients lips and eyelids several months ago. She also notes that he seems to suffer from frequent constipation and appears weaker than many of his peers. The boys past medical history is unremarkable. His maternal aunt, maternal uncle, and maternal grandmother have a history of colorectal cancer and his father and paternal grandmother have a history of thyroid cancer. His height and weight are in the 85th and 45th percentiles, respectively. His temperature is 99F 37.1C, blood pressure is 11065 mmHg, pulse is 90min, and respirations are 18min. On examination, he has an elongated face with protruding lips. There are numerous sessile painless nodules on the patients lips, tongue, and eyelids. This patients condition is most strongly associated with a mutation in which of the following genes?? A: c-KIT, B: MEN1, C: NF1, D: NF2, E: RET,  <response>: Based on the description of the patients symptoms and family history, this seems to be a case of multiple endocrine neoplasia type 2A MEN2A. The key findings are the skin growths on the lips and eyelids, constipation, weakness, and family history of thyroid cancer. MEN2A is caused by mutations in the RET proto-oncogene. Therefore, the answer is likely to be RET.E: RET 