Final answer:
Exercise is one condition associated with stable tachycardia with a pulse, as it is a normal physiological response where the heart rate increases to meet the body's increased oxygen demand.
Step-by-step explanation:
Tachycardia, which is defined as a heart rate (HR) above 100 beats per minute (bpm), can be associated with various conditions. While tachycardia in a resting patient is not normal, there are situations when an elevated HR is expected. Exercise is one condition associated with stable tachycardia with a pulse. During exercise, the body's demand for oxygen increases, and the heart rate rises to meet this demand.
Other factors such as dehydration, anxiety, and heart failure can also be associated with tachycardia. However, of the options provided, exercise is the normal physiological response that would explain a stable tachycardia with a pulse. Treatment for tachycardia depends on its underlying cause and may include interventions like medications or surgery.