Final answer:
Mandatory employee meetings held by employers during pre-election campaigns to present anti-union messaging are called captive audience meetings.
Step-by-step explanation:
When employees are required to attend a meeting to hear a presentation by the employer during a pre-election campaign, the meeting is called a captive audience meeting.
This term describes a situation where attendance is mandatory, and the workforce is a 'captive' audience to the employer's messaging, which is often anti-union in nature. Such meetings are part of management's efforts to influence the employees' voting behavior in a union election. They stand in contrast to more democratic processes like caucuses or secret ballots, where employees have the freedom to express their views or votes without undue pressure.