The correct answer is "A".
The Hundred Years War was fought between the Kingdom of England and France between 1337 and 1453. Although the War resulted in the victory for the French, as they were able to expel the English invasion from mainland Europe, the English had 3 initial victories at Crecy, Poitiers, and Agincourt. These victories were mainly due to the improved weaponry the invading English forces used against the local French soldiers. The Battle of Crecy saw the introduction of the Longbow as a key weapon for warfare.