Steven recently purchased a meat-packing plant in which the employees are unionized. steven confesses that he knows almost nothing about labor law. in advising him about the national labor relations act, you should tell him that he is prohibited from all of the following except:

a. refusing to bargain collectively with the duly designated representative of the employees.
b. dominating a labor organization.
c. protecting employees' right to strike.
d. interfering with employee efforts to unionize.