Answer:
b. rightward shift in supply and demand
Explanation:
A rightward shift in the supply curve means an increase in supply. All things being equal, this leads to an increase in Quanitity supplied and a fall in price. Also, a rightward shift in the demand curve me and an increase in Quanitity demanded and an increase in price. Taking these two effects together, equilibrium quantity rises but there's an indeterminate effect on price.
Please check the attached image for a graph of this explanation.
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