Final answer:
The significant change in Indian Ocean commerce from 650 CE to 1750 CE was the dominance of European colonial powers in trade, which led to the creation of global trade networks and the decline of traditional land-based routes like the Silk Road.
Step-by-step explanation:
A significant change in commerce within the Indian Ocean region from 650 CE to 1750 CE is best described by B) The dominance of European colonial powers in controlling trade. During this period, European nations such as Portugal, the Netherlands, England, and France embarked on voyages of exploration, establishing maritime trade networks that contributed to the globalization of trade. The Age of Exploration led Europeans to seek an all-water route to Asia to avoid the costly and perilous Silk Road, resulting in an interconnected trade network spanning the globe.
European colonial dominance was marked by the challenge and eventual control over key trade routes and ports, causing a shift in power dynamics within the Indian Ocean trade. The European quest for alternative routes was fueled by the desire to bypass the existing overland routes and the taxes levied by intermediary Ottoman and Muslim traders. The Europeans' success in establishing direct water routes to the East signified a major shift from regional to global trade dynamics, which became central to commerce during this era.