## Core Concept
Atrial myxomas are the most common type of primary heart tumor in adults. They are typically benign and arise from the interatrial septum. Understanding their characteristics and clinical presentation is crucial for diagnosis and management.

## Why the Correct Answer is Right
Atrial myxomas usually occur in the left atrium and are often attached to the interatrial septum near the fossa ovalis. They can cause symptoms by obstructing blood flow or by emulating systemic symptoms due to production of interleukin-6 (IL-6), leading to constitutional symptoms such as fever, weight loss, and elevated erythrocyte sedimentation rate (ESR).

## Why Each Wrong Option is Incorrect
To accurately address this question, the specific details of each option (A, B, C, D) regarding atrial myxomas need to be evaluated. However, since the question and specific details of the options are not provided, let's hypothetically analyze:

- **Option A:** If a statement claims that atrial myxomas are malignant, this would be incorrect because they are typically benign.
- **Option B:** If a statement says they are most commonly found in the right atrium, this might be incorrect because they are most commonly found in the left atrium.
- **Option C:** If a statement mentions that they can cause embolic phenomena, this would be correct and thus not the answer.
- **Option D:** If a statement suggests they are associated with systemic symptoms, this would also be correct.

## Clinical Pearl / High-Yield Fact
A key clinical pearl is that atrial myxomas can mimic a variety of conditions, including infective endocarditis or even autoimmune diseases, due to their ability to produce IL-6, leading to systemic symptoms. They are also associated with a familial syndrome known as the Carney complex, which includes myxomas, endocrine abnormalities, and skin changes.

## Correct Answer: B.