<prompt> Please answer with one of the option in the bracket. Write reasoning in between . Write answer in between .Q:A 13-year-old girl is brought to the physician by her mother because of a 1-year history of worsening clumsiness. Initially, she swayed while walking; over the past 3 months, she has fallen 4 times. Ophthalmic examination shows a horizontal nystagmus. Proprioception and vibratory sensation are decreased in the distal extremities. Deep tendon reflexes are 1 bilaterally. Further evaluation of the patient shows a genetic disorder involving an iron-binding mitochondrial protein encoded on chromosome 9. Which of the following findings is most likely to also be seen in this patient?? A: Hyperpigmented skin, B: Telangiectasias, C: Hammer toes, D: Myoclonic jerks, E: Adenoma sebaceum,  <response>: Based on the description in the question stem, the patient is exhibiting symptoms of progressive ataxia and loss of coordination such as swaying while walking, falling, nystagmus involuntary eye movement, decreased proprioception and vibratory sensation, and diminished reflexes. This suggests a neurodegenerative disorder affecting the cerebellum and peripheral nerves. The question states that the patient has a genetic disorder involving an iron-binding mitochondrial protein encoded on chromosome 9. This clearly points to Friedreich ataxia, an autosomal recessive disorder caused by mutations in the FXN gene on chromosome 9q13. The FXN gene codes for the protein frataxin, which is involved in iron transport in mitochondria. Deficiency of frataxin leads to mitochondrial dysfunction and neurodegeneration.Of the answer choices provided, hammer toes choice C is a common clinical finding in patients with Friedreich ataxia, along with scoliosis and high-arched feet. Hammer toes result from imbalance between intrinsic foot muscles due to the progressive neurodegeneration. The other choices do not describe typical findings in Friedreich ataxia.C: Hammer toes 