Which of the following is an example of an employer unfair labor practice?

A、
Katrina, the union head, expels members for crossing a picket line that is unlawful.
B、
Jelle, a manager, threatens to close down a plant if organized by a union.
C、
Wayne, a manager, prohibits mass picketing when nonstriking employees are physically barred from entering the plant.
D、
Gerardo, a union member, causes the discharge of an employee, Noah, who spoke out against a contract proposed by the union.
E、
Ila, an employee representative, tricks her employer by including illegal provisions in a contract.