**Core Concept**
Fragile X syndrome is a genetic disorder caused by an expansion of the CGG repeat in the FMR1 gene on the X chromosome. This leads to the silencing of the gene and a deficiency of the fragile X mental retardation protein (FMRP), resulting in various physical and cognitive abnormalities.

**Why the Correct Answer is Right**
Fragile X syndrome is characterized by physical features such as a long face, large ears, and macroorchidism (enlarged testicles) in males. Cognitive impairments range from mild to severe, with intellectual disability, attention deficit hyperactivity disorder (ADHD), and autism spectrum disorder (ASD) being common comorbidities. The FMRP plays a crucial role in regulating synaptic plasticity and mRNA translation, and its deficiency leads to disrupted neuronal function and development.

**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because Fragile X syndrome is indeed associated with anxiety and mood disorders, such as autism spectrum disorder and attention deficit hyperactivity disorder.
**Option B:** Incorrect because Fragile X syndrome is characterized by a long face, large ears, and macroorchidism in males.
**Option C:** This option is not provided, but we will assume it is incorrect based on the context. Please provide the correct options for completion.
**Option D:** This option is not provided, but we will assume it is incorrect based on the context. Please provide the correct options for completion.

**Clinical Pearl / High-Yield Fact**
Fragile X syndrome is the most common cause of inherited intellectual disability, affecting approximately 1 in 4,000 males and 1 in 6,000 females. It is also a significant risk factor for autism spectrum disorder and ADHD.

**Correct Answer:**
(Replace with actual answer choice, e.g., C, D, etc.)