What management tactic involves preventing workers from working?

The correct answer is "Lockout," which is a management tactic used by employers to prevent workers from working, usually during labor disputes. During a lockout, the employer suspends work and denies employees access to the workplace. Typically, this tactic is employed to pressure workers during negotiations or disputes, often in response to a union strike.

In contrast to lockouts, a strike is initiated by workers to protest working conditions or to demand better terms. Unionization refers to the process by which workers come together to form a union, aiming to gain collective bargaining power. Collective bargaining is the process of negotiation between employers and union representatives regarding wages, working conditions, and other employment terms. Therefore, while the other options involve aspects of labor relations and negotiations, a lockout specifically denotes the act of management preventing workers from performing their jobs.