15. What is Gerhardt's sign (aka Sailer's sign)?

A. A decrease in diastolic blood pressure of 15 mmHg when the arm is held above the head.

B. Pulsation of the spleen in the presence of splenomegaly.

C. Bobbing of the head with each heartbeat (like a bird walking).

D. Exaggeration of the murmur of aortic regurgitation with leaning forward at end expiration