Answer:
d. the demand curve shifted to the right
Step-by-step explanation:
As more people migrated west during the gold rush, there would be an increase in demand in most markets as a result of the population increase. This would lead to a shift of the demand curve to the right.
For example, in the housing market, more people would needs houses to leave in, the demand for houses would increase and the demand curve would shift to the right.
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