The idea that immigration lowers the wages and employment of native-born workers is based on: a) A model of supply and demand where an increase in the demand for labor will lower the wage rate and the quantity of native-born employed. b) A model of supply and demand where an increase in the supply of labor will lower the wage rate and the quantity of native-born employed. c) The findings of research studies on the actual impact of immigrants on local labor markets. d) Both (b) the supply and demand model and (c) the findings of research