Which intervention would be helpful in relieving morning discomfort associated with rheumatoid arthritis?

A. Sleeping with two pillows under the head may not specifically relieve joint stiffness or discomfort. B. Taking a warm bath the evening before may help relax muscles but does not directly address morning stiffness. C. Applying moist heat in the morning helps relax stiff joints and muscles, reducing discomfort common with rheumatoid arthritis. D. Wearing splints at night is more useful for preventing flexion contractures rather than relieving morning discomfort.