To solve this question, the user needs to be familiar with the definitions of culture, subculture, and multi-ethnic society.

Culture refers to the shared beliefs, values, customs, behaviors, and artifacts that characterize a group or society.

A subculture is a smaller cultural group within a larger culture that shares some of the larger culture's characteristics but also has its own distinct values, norms, beliefs, behaviors, and artifacts.

A multi-ethnic society is a society that contains multiple ethnic groups, each with its own unique cultural characteristics.

Based on the given definition, the correct answer is:

B. subculture.

This is because the definition provided describes a group that is distinguishable from other groups in a society by the fact that its members share a common identity, food tradition, dialect or language, and other cultural traits that come from their common ancestral background and experience. This aligns with the definition of a subculture, which is a smaller cultural group within a larger culture that shares some of the larger culture's characteristics but also has its own distinct values, norms, beliefs, behaviors, and artifacts.