Which of the Following Is an Unfair Labor Practice on the Part

Which of the following is an unfair labor practice on the part of an employer?

A) An employer creates employee groups within the organization and asks employees to participate in setting wages,hours,and terms and conditions of employment.
B) If two unions are vying to organize a group of workers;an employer neither recognizes one to avoid dealing with the other nor expresses a preference for one over the other.
C) An employer creates a company-sponsored union and bargains with it.
D) An employer discriminates in hiring,assignment,or other terms of employment on the basis of union membership.