A 10-year-old child with Fanconi’s syndrome.
**Core Concept**
Fanconi's syndrome is a **renal tubular disorder** characterized by impaired reabsorption of glucose, amino acids, and phosphate in the proximal tubules. This leads to excessive loss of these substances in the urine. The underlying defect involves the **proximal convoluted tubule**.
**Why the Correct Answer is Right**
Since the question is incomplete, let's focus on the key aspects of Fanconi's syndrome. The condition results from a dysfunction in the **sodium-potassium pump** and **cotransport mechanisms**, leading to impaired reabsorption. This affects the reabsorption of glucose, amino acids, phosphate, and bicarbonate, causing their excessive urinary excretion.
**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific details of option A, we cannot directly address why it's incorrect.
**Option B:** Similarly, option B's incorrectness cannot be specified.
**Option C:** Option C would be incorrect if it suggested a different primary site of dysfunction or an unrelated condition.
**Option D:** Likewise, option D's incorrectness is unspecified due to lack of details.
**Clinical Pearl / High-Yield Fact**
A key point to remember about Fanconi's syndrome is its association with **cystinosis**, a lysosomal storage disorder. This condition often presents with Fanconi's syndrome in children.
**Correct Answer:**