Unions tend to increase the disparity in pay between insiders and outsiders by ?

• A. increasing the wage in the Unionized sector, Which may create a decrease in the supply of workers in the non-unionized sector
• B. Increasing the demand for workers in the Unionized sector
• C. decreasing the demand for workers in the Unionized sector
• D. Increasing the wage in the Unionized sector which may create an increase in the supply of workers in the non-unionized sector