"Don't buy where you can't work" was the protest slogan of

“The "Don't Buy Where You Can't Work" movement, also known as the "Buy Where You Can Work" movement, emerged in major northern U.S. cities during the Great Depression to protest black unemployment rates that often were double or triple the national average.“

Explanation:

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a.tensions between the colonial elites and the backcountry men of virginia.

c or d both can be the answer