You are answering a USMLE-style medical question. Question: A 14-year-old boy is brought to the physician because of an increasing difficulty in hearing over the past several months. His mother says they have to speak at a higher volume for him to understand them. He also complains of having difficulty reading his favorite books because he is not able to see the words clearly. His father received a renal transplant in his 20s. The vital signs are within normal limits. The physical examination shows no abnormalities. Laboratory studies show: Serum Urea nitrogen 15 mg/dL Creatinine 1.0 mg/dL Urine Blood 1+ Protein 1+ RBC 15–17/hpf WBC 1–2/hpf The audiometry shows bilateral high-frequency sensorineural hearing loss. The ophthalmologic examination shows anterior lenticonus. Which of the following best explains these findings? Options: A) Alport syndrome B) Fabry’s disease C) Von Hippel-Lindau disease D) Tuberous sclerosis Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.