**Core Concept**
The question is testing knowledge of genetic disorders. X-linked dominant inheritance is a type of pattern where a single copy of the mutated gene on the X chromosome is sufficient to cause the condition, and both males and females can be affected. This contrasts with X-linked recessive inheritance, where only males are typically affected.

**Why the Correct Answer is Right**
The correct answer is Hemophilia A. Hemophilia A is caused by a deficiency in factor VIII, a protein involved in blood clotting. The gene for factor VIII is located on the X chromosome. In females, having one mutated gene can lead to reduced levels of factor VIII, resulting in mild hemophilia. However, males with one mutated gene will have no functional factor VIII, leading to severe hemophilia. This is a classic example of X-linked dominant inheritance.

**Why Each Wrong Option is Incorrect**
**Option A:** Becker Muscular Dystrophy is an X-linked recessive disorder, not dominant. It affects males primarily and is caused by mutations in the dystrophin gene.

**Option B:** Fragile X Syndrome is an X-linked dominant disorder, but it is not the correct answer. It is caused by an expansion of the CGG repeat in the FMR1 gene, leading to intellectual disability and other physical characteristics.

**Option C:** This option is not a valid choice.

**Clinical Pearl / High-Yield Fact**
When considering X-linked dominant disorders, remember that both males and females can be affected, although males are typically more severely affected due to having only one X chromosome.

**Correct Answer: B. Fragile X Syndrome**