The answer is: It stopped the Muslim advance into Western Europe.
This is incorrect. Charles Martel never became King of France. He was the Mayor of the Palace and a de facto ruler, but he did not hold the title of king. His grandson, Charlemagne, later became Emperor, but this was after Martel's time.
This is correct. The Battle of Tours, fought in 732 AD, was significant because it halted the advance of Muslim forces into Western Europe. Charles Martel's victory is often credited with preserving Christianity in Europe and preventing the spread of Islam beyond the Iberian Peninsula.
This is incorrect. The Battle of Tours took place before Charlemagne's time. Charlemagne, who was Charles Martel's grandson, did later extend his empire into parts of Spain, but this was not a direct result of the Battle of Tours.
This is incorrect. The Battle of Tours had the opposite effect; it prevented Muslim forces from gaining control of France and further advancing into Western Europe.