What is it called when management refuses to allow bargaining unit members on the premises during a strike?

The correct term for when management refuses to allow bargaining unit members on the premises during a strike is a lockout. This action is typically taken by employers to prevent striking workers from returning to work, which is an attempt to pressure the union into conceding to management's demands during negotiations.

A lockout is a strategic measure employed by management, especially during disputes over labor contracts or working conditions. The fundamental purpose of a lockout is to assert control over the work environment and limit the operations of the business until an agreement is reached.

The other terms listed do not accurately describe this scenario. "Shutout" is not a widely recognized term in labor relations related to this context, and "lock in" refers to a different concept, often related to contractual agreements or commitments rather than an employer's action during a strike. As for the choice stating "All of the above," it would imply that the other terms are synonyms or interchangeable with the term lockout, which is not the case. Thus, lockout is the most precise and recognized terminology to describe this situation in labor relations.