A 1-year-old girl is noted to have a continuous murmur, loudest at the left sterna edge. She is not cyanosed. A diagnosis of patent ductus arteriosus is suspected.. Collapsing pulse

A 1-year-old girl is noted to have a continuous murmur, loudest at the left sterna edge. She is not cyanosed. A diagnosis of patent ductus arteriosus is suspected. What pulse abnormality is most associated with this condition?
A. Collapsing pulse***
B. Bisferiens pulse
C. Pulsus parodoxus
D. 'Jerky' pulse
E. Pulsus alternans.