## **Core Concept**
The question pertains to Mucopolysaccharidosis (MPS), a group of metabolic disorders caused by the deficiency of enzymes needed to degrade and recycle sugar molecules. These disorders result in the accumulation of glycosaminoglycans (GAGs) within cells and tissues, leading to cellular dysfunction.

## **Why the Correct Answer is Right**
The correct answer, **Hunter syndrome (MPS II)**, is characterized by the deficiency of the enzyme iduronate-2-sulfatase. This condition primarily affects males due to its X-linked recessive inheritance pattern. A key clinical feature of Hunter syndrome is the absence of corneal clouding, which distinguishes it from other types of MPS, such as Hurler syndrome (MPS I) and Hurler-Scheie syndrome (MPS I S), where corneal clouding is a prominent feature.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is incorrect because **Hurler syndrome (MPS I)** is known for causing corneal clouding among its clinical manifestations.
- **Option B:** This option is incorrect as it is not specified; however, other MPS types like **Hurler-Scheie syndrome (MPS I S)** also present with corneal clouding.
- **Option D:** This option is incorrect because **Sanfilippo syndrome (MPS III)**, which includes several subtypes, does not characteristically present with corneal clouding but is not the best answer here given the specifics of the question.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that **Hunter syndrome (MPS II)** is one of the few MPS types that do not present with corneal clouding, making it distinguishable from other MPS disorders. This is crucial for diagnosis and management.

## **Correct Answer:** . **Hunter Syndrome**