When we use "race" as a sociological idea (instead of a biological concept), then race is subdivided into smaller cultural classifications called
a. species
b. race
c. breeding population
d. ethnic group
e. none of the above

d. ethnic group

Explanation:

The race can be categorized into a cultural classification as ethnic group. This helps in identification of the population of single kind of organisms into a single group which exhibit a common language, culture, society, ancestry and nation as well. The ethnic group is appropriate in terms of biological concepts.

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