What region did Charlemagne's empire extend to at its height?

Charlemagne's empire, at its height during the late 8th and early 9th centuries, encompassed a significant portion of Western Europe. The correct answer highlights the specific geographic boundaries of his realm, which stretched from Northern Spain to western Germany. This area includes modern-day countries such as France, Germany, and parts of Italy.

Charlemagne's conquests and administrative reforms helped solidify a unified Christian empire known as the Carolingian Empire. By securing control over a vast territory that included important trade routes and cultural centers, he laid the groundwork for what would later evolve into several European nations.

The other regions mentioned in the incorrect options do not accurately describe the extent of Charlemagne's empire. The areas listed in those choices either represent regions outside of his control or suggest a geographic span that does not align with historical records of his rule.