**Core Concept**
The cloudy cornea is a feature of certain mucopolysaccharidoses, a group of genetic disorders caused by the deficiency of lysosomal enzymes involved in the breakdown of glycosaminoglycans. This accumulation of glycosaminoglycans leads to corneal clouding, among other systemic manifestations.

**Why the Correct Answer is Right**
All three options, Hurler's disease, Morquio's disease, and Maroteaux-Lamy disease, are mucopolysaccharidoses characterized by the accumulation of glycosaminoglycans due to enzyme deficiencies. In Hurler's disease (alpha-L-iduronidase deficiency), Morquio's disease (beta-galactosidase or N-acetylgalactosamine-6-sulfatase deficiency), and Maroteaux-Lamy disease (arylsulfatase B deficiency), the accumulation of dermatan sulfate, keratan sulfate, and chondroitin-6-sulfate, respectively, leads to corneal clouding. The cloudy cornea is a key diagnostic feature of these disorders, often detected in early childhood.

**Why Each Wrong Option is Incorrect**
**Option A:** Hurler's disease primarily affects the central nervous system, leading to intellectual disability, but corneal clouding is a key feature, so this option is incorrect.
**Option B:** Morquio's disease is characterized by skeletal dysplasia, particularly of the spine and limbs, but corneal clouding is a distinctive feature, so this option is incorrect.
**Option C:** Maroteaux-Lamy disease is characterized by skeletal and joint involvement, but corneal clouding is a key diagnostic feature, so this option is incorrect.

**Clinical Pearl / High-Yield Fact**
All mucopolysaccharidoses have a similar clinical presentation, including corneal clouding, intellectual disability, and skeletal abnormalities, but the specific enzyme deficiency and glycosaminoglycan accumulation vary between the disorders.

**✓ Correct Answer: D. All of the above**