## Core Concept
Fragile X syndrome is a genetic disorder caused by a mutation on the X chromosome, leading to intellectual disability, behavioral and learning challenges, and various physical characteristics. It is the most common cause of inherited intellectual disability. The mutation involves an expansion of the CGG repeat in the FMR1 gene, leading to its silencing and the absence or deficiency of the FMRP protein.

## Why the Correct Answer is Right
The correct answer, which is not provided, would typically relate to a specific false statement about Fragile X syndrome. Generally, accurate statements about Fragile X include its genetic cause, the role of the FMR1 gene and FMRP protein, and its clinical manifestations. Without the specific options, we focus on the general understanding that Fragile X syndrome is characterized by intellectual disability, a long face, large or protruding ears, and in males, macroorchidism post-puberty.

## Why Each Wrong Option is Incorrect
- **Option A:** Without the specific details of Option A, we can't directly address its inaccuracy. However, any statement contradicting the established genetic, molecular, or clinical facts about Fragile X syndrome would be incorrect.
- **Option B:** Similarly, Option B's inaccuracy would stem from contradicting known aspects of Fragile X syndrome, such as its inheritance pattern (X-linked dominant), the role of the FMR1 gene, or common physical and behavioral features.
- **Option C:** This option would be incorrect based on the same principle of contradicting established knowledge about Fragile X syndrome.
- **Option D:** As with the other options, its incorrectness would be due to a contradiction of verified information regarding Fragile X syndrome.

## Clinical Pearl / High-Yield Fact
A key point to remember is that Fragile X syndrome is caused by an expansion of the CGG repeat in the FMR1 gene on the X chromosome. This condition leads to the absence or deficiency of the FMRP protein, which is crucial for brain development and function. A significant clinical feature in males is the presence of macroorchidism (enlarged testicles) post-puberty.

## Correct Answer: D.