${?}_{\_\_\_\_\_\_\text{a}\text{r}\text{e}\text{p}\text{r}\text{o}\text{t}\text{e}\text{c}\text{t}\text{e}\text{d}\text{f}\text{r}\text{o}\text{m}\text{u}\text{n}\text{f}\text{a}\text{i}\text{r}\text{l}\text{a}\text{b}\text{o}\text{r}\text{p}\text{r}\text{a}\text{c}\text{t}\text{i}\text{c}\text{e}\text{s}}$bytheNationalLaborRelationsActof1935(NLRA).a.Onlyemployerswithlessthan15employeesb.Onlyindependentcontractorsc.Onlyemployeeunionleadersd.Onlyemployees