Which of the following best describes the characteristics of the left ventricle in diastolic heart failure?

A. Thin and flexible walls are not typical in diastolic heart failure. B. Weak and non-contractile describes systolic heart failure. C. In diastolic heart failure, the left ventricle becomes thickened and stiff, impairing its ability to relax and fill properly. D. Enlarged and dilated ventricles are characteristic of systolic heart failure, not diastolic.