Answer:
a. Restriction of right to self-organization.
In the scenario, Mr. Cruz is seen to be restricting the right of Mirna, his employee, to self-organize and join a labor organization of her choice. This constitutes an unfair labor practice under the provisions of the National Labor Relations Act (NLRA). Employees have the right to form, join, or assist labor organizations of their choosing, and employers cannot interfere with or restrict these rights.