## **Core Concept**
Von Willebrand's disease (VWD) is a genetic disorder caused by deficiency or dysfunction of von Willebrand factor (VWF), a crucial protein for blood clotting. The disease affects both males and females and is characterized by easy bruising, nosebleeds, and heavy menstrual periods. The inheritance pattern of VWD is primarily autosomal.

## **Why the Correct Answer is Right**
The correct answer, **Autosomal Dominant**, is right because the most common type of VWD, known as Type 1, follows an autosomal dominant pattern of inheritance. This means a single copy of the mutated gene is enough to cause the condition. Type 1 VWD is characterized by a partial deficiency of VWF, and it accounts for the majority of VWD cases. The autosomal dominant inheritance pattern explains why the disease can affect both males and females equally and can be passed down from either parent.

## **Why Each Wrong Option is Incorrect**
- **Option A: X-linked Recessive** - This is incorrect because VWD does not predominantly affect males (as seen in hemophilia A and B) and is not linked to the X chromosome. It affects both genders equally.
- **Option B: Autosomal Recessive** - This is incorrect for VWD because, although some types like Type 3 VWD follow an autosomal recessive pattern, the commonest form, Type 1, is autosomal dominant.
- **Option D: Sporadic** - This is incorrect because, while some cases of VWD may appear sporadic due to new mutations, the disease commonly follows a familial pattern consistent with autosomal dominant inheritance.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that Type 1 VWD, the most common form, often presents with mild symptoms and is usually inherited in an **autosomal dominant** manner. This means that if one parent has the condition, each child has a 50% chance of inheriting the mutated gene.

## **Correct Answer: C. Autosomal Dominant**