What is defined as people who share similar physical characteristics?

The correct answer is race, as it specifically refers to groups of people who are defined based on shared physical characteristics, such as skin color, facial features, and hair type. These biological traits have historically been used to categorize individuals into different racial groups. The concept of race is often intertwined with social and cultural implications, but at its core, it is based on observable physical characteristics that distinguish one group from another.

In contrast, ethnicity refers to shared cultural traits such as nationality, language, and customs, which do not necessarily align with physical appearance. Culture encompasses the beliefs, behaviors, values, and practices of a group and is more focused on learned attributes rather than inherent physical traits. Mores relate to the norms and values within a society that dictate what is considered morally acceptable or unacceptable, which again does not pertain to physical characteristics. Therefore, race is the most accurate term when describing groups distinguished by shared physical traits.