Your answer is 'B. Skilled military leader'.
Answer: The Janissaries made significant contributions to many important Ottoman victories, among them the conquest of Constantinople in the spring of 1453, the battle against the Iranian Safavids at Chaldiran in 1514, and the defeat of the Mamluk armies at Marj Dabik in 1516.
Answers:
The exchange introduced a wide range of new calorically rich staple crops to the Old World—namely potatoes, sweet potatoes, maize, and cassava. The primary benefit of the New World staples was that they could be grown in Old World climates that were unsuitable for the cultivation of Old World staples.
There were actully 4. Romania, Serbia, Montenegro, and Bulgaria. This was because of The Congress of Berlin.
