What is an autonomous region in China?

An autonomous region in China is indeed a territory unit that has the same administrative status as a province. These regions are specifically designated to recognize and provide certain rights to ethnic minorities within China. Autonomous regions are designed to grant a degree of administrative autonomy to the local population, particularly for ethnic groups that have distinct cultural, linguistic, or historical identities. This helps to accommodate the diverse ethnic landscape of China and allows these regions to have some level of self-governance, including the ability to make local laws and policies in certain areas, such as education and cultural affairs. This status is meant to promote respect for cultural diversity while integrating these regions within the broader governance framework of the People's Republic of China.

The other options do not accurately capture the definition of an autonomous region. For instance, some regions may indeed have ethnic minorities, and being ruled solely by local governments is not a feature of autonomous regions, as central government authority still extends to them. Furthermore, the concept of high foreign investment is unrelated to what defines an autonomous region, focusing more on economic factors rather than administrative or political structure.