A、To help mariners. B、To improve ship design and sailing methods. C、To study astronomy and mathematics. D、To improve his own ski

The modern sailing ship was developed by a man who never went to sea. He was Prince Henry of Portugal, the younger son of the Portuguese King and an English princess.
    Prince Henry lived in the 15th century. As a boy he became devoted to the sea, and he dedicated himself to improving the design of ships and the methods of sailing them. In 1416, Henry founded a school for mariners, to which he invited everyone who could help him--Jewish astronomers, Italian and Spanish sailors, and Arab mathematicians and map makers who knew how to use the crude compass of the day and improve it.
    Henry’s goal was to design and equip vessels that would be capable of making long ocean voyages without having to hug the shore. The caravel carried more sail and was longer and slimmer than any ship then made, yet was tough enough to withstand gales at sea. He also developed the carrack, which was a slower ship, but one that was capable of carrying more cargo.
    To Prince Henry the world owes credit for the development of craft that made oceanic exploration possible. He lives in history as "Prince Henry the Navigator".