Which of the Following Is Correct

Multiple Choice

Which of the following is correct?

A) In unionized industries, wages are below the level that would prevail in competitive markets.
B) The introduction of a union in an industry reduces the quantity of labor demanded in that industry, causes some workers in that industry to be unemployed, and reduces wages in the rest of the economy.
C) There is a strong consensus among economists that unions are bad for the U.S. economy.
D) All of the above are correct.