Answer :
"A. He was defeated at Waterloo and was exiled to St. Helena" is correct. Napoleon famously lost this battle in what would prove to be a marker of the extent of his military reach.
The correct answer is A, as Napoleon was defeated at Waterloo and was exiled to St. Helena.
The Battle of Waterloo was a battle that took place on June 18, 1815 near Waterloo, a town in present-day Belgium located about twenty kilometers south of Brussels, between the French army, commanded by the Emperor Napoleon Bonaparte, against the British, Dutch and German troops, led by the Duke of Wellington, and the Prussian army of Field Marshal Gebhard von Blücher.
After his return from the exile on the island of Elba, Napoleon decided to invade the Netherlands, a meeting place for the troops of the new alliance. The battle was a defeat for Napoleon, and meant the definitive end of the Napoleonic wars.
After Waterloo the allied troops entered France searching for Napoleon. On July 1, Von Blücher occupied Versailles, on July 8 the crown of Louis XVIII was restored and two days later, on July 10, Napoleon surrendered. He went exiled on July 26 on the island of St. Helena, located in the middle of the Atlantic, where he died six years later.