The best explanation for the rise in economist salaries and the fall in accounting salaries would be (B) The supply of economists must have decreased, and the supply of accountants must have increased.
When there is a decrease in the supply of a commodity, its prices will go up. The salaries of economists went up because the number of economists available, decreased.
When there is an increase in the supply of something, the price will decrease. This is why the accountants saw their salaries decrease - the number of accountants available increased.
In conclusion, option B is correct.
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