Answer:
C. Beer and Marijuana are complementary goods
Explanation:
Since an increase in the price of beer is reducing the demand for marijuana this means that people were buying both at a time, now that the price of beer is higher they cannot afford both so are buying beer only. Therefore we can say that Beer and Marijuana are complementary goods.
If the increase in beer price led to an increase in Marijuana demand, then that would make them substitute goods since people are <u><em>substituting</em></u> one vice for another cheaper one.
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