A 10-year-old male with short stature is being evaluated for progressive neuropathy. Deep tendon reflexes are decreased, and vibratory sensation and proprioception are impaired. He has ataxia and a spastic gait. Ophthalmologic examination reveals decreased vision in dim light and pigmentary retinal degeneration. He has a history of frequent diarrhea with fatty stools. A serum lipid profile shows: Cholesterol 33 mg/dL (normal 132-220), Triglyceride 0 mg/dL (normal 32-150), HDL cholesterol 28 mg/dL (normal 34-86). Genetic testing reveals a mutation in a gene encoding a protein necessary for normal lipoprotein metabolism. In which of the following genes is this mutation most likely?

1. A)ApoB100 receptor gene
2. B)Lecithin acyl cholesterol transferase (LCAT) gene
3. C)ApoB geneGABARITO
4. D)ApoC2 gene
5. E)ApoE gene