Which of the following signs would most likely indicate an embolism?

Sudden shortness of breath is a key indicator of an embolism, particularly a pulmonary embolism, which occurs when a blood clot travels to the lungs. The abrupt onset of difficulty in breathing is often accompanied by chest pain and can be a result of reduced blood flow or oxygenation due to the obstruction in the pulmonary artery. This symptom prompts immediate medical evaluation because it signals a potentially life-threatening condition that requires urgent intervention.

The other signs listed, while they can indicate various medical issues, do not directly suggest an embolism. Localized swelling and redness may indicate issues such as thrombophlebitis or cellulitis. A persistent cough with yellow sputum can be indicative of a respiratory infection, such as bronchitis or pneumonia, rather than an embolism. Fever with chills typically signals infection or inflammatory processes rather than a blocked blood vessel. Thus, sudden shortness of breath distinctly aligns with the symptoms of an embolism, underscoring the importance of recognizing this sign in clinical settings.