Which is best described as the inability of the heart to pump an adequate amount of blood to the systemic circulation at normal filling pressures?
Correct Answer: C
Rationale: Heart failure is best described as the inability of the heart to pump an adequate amount of blood to the systemic circulation at normal filling pressures. This results in the inefficient delivery of oxygen and nutrients to the body's tissues, leading to symptoms such as fatigue, shortness of breath, and fluid retention. Pulmonary congestion, systemic venous congestion, and congenital heart defects can be associated with heart failure but are not the primary definition of the condition.