Refusing to buy from Jewish shops was what kind of participation by ordinary people?

Correct answer: Participation in economic boycott

Refusing to buy goods from Jewish shops was an everyday form of economic participation in the persecution of Jews. A boycott means deliberately avoiding a person, shop, or group as a way of applying pressure. When ordinary customers stopped purchasing from Jewish shopkeepers, those shops lost income and their owners were pushed into social and economic isolation. Thus, this action was not a cultural celebration, scientific reform, or judicial independence; it directly affected people’s livelihood through the economy.

The question asks what kind of participation this refusal represented. The important clue is the act of not buying, which concerns trade, customers, sales, and income. Therefore, the correct choice is C, participation in an economic boycott. Even if a person did not directly commit physical violence, joining such a boycott helped the Nazi policy of excluding and weakening Jews. This shows how ordinary daily choices could contribute to crimes against humanity.