(2) C.N. Barnard Explanation: Christiaan Neethlirig Barnard was a South African cardiac surgeon who performed the world's first successful human-to-human heart transplant. He performed the world's first human heart transplant operation on 3 December 1967, in an operation assisted by his brother, Marius Barnard; the operation lasted nine hours and used a team of thirty people. The patient, Louis Washkansky, was a 54-year-old grocer, suffering from diabetes and incurable heart disease.