**Core Concept**
Raynaud's disease is a vasospastic disorder characterized by episodic vasospasm of the arteries supplying the extremities, typically the fingers and toes, in response to cold or emotional stress. This condition is often associated with an exaggerated response of the sympathetic nervous system.

**Why the Correct Answer is Right**
Option B, "Positive antinuclear antibodies," is incorrect because Raynaud's disease is not typically associated with autoimmune disorders, which are often characterized by the presence of antinuclear antibodies. Raynaud's disease is a primary condition, meaning it is not secondary to another underlying disease process, such as systemic lupus erythematosus or scleroderma, which can also present with vasospastic symptoms. In these autoimmune conditions, the presence of antinuclear antibodies is a diagnostic clue.

**Why Each Wrong Option is Incorrect**
**Option A:** Raynaud's disease is indeed more common in females, with a female-to-male ratio of approximately 3:1. This is likely due to hormonal influences, but the exact mechanisms are not fully understood.
**Option C:** Raynaud's phenomenon is the term used to describe vasospastic episodes in response to cold or stress, which can be primary (Raynaud's disease) or secondary to another underlying condition (Raynaud's phenomenon). The most common cause of Raynaud's phenomenon is indeed primary Raynaud's disease.
**Option D:** While Raynaud's disease is generally considered to have a good prognosis, with treatment aimed at managing symptoms and preventing complications, some patients may experience significant morbidity, particularly if left untreated or inadequately managed.

**Clinical Pearl / High-Yield Fact**
A key clinical pearl in managing Raynaud's disease is to encourage patients to maintain a warm environment, avoid cold exposure, and engage in smoking cessation, as smoking is a significant risk factor for the development and progression of vasospastic disorders.

**✓ Correct Answer: B. Positive antinuclear antibodies**