At Corpceton, a plastic products manufacturing company, two to three newly hired machine operators are assigned to senior machine operators who train them for a few weeks. After the trainees complete three months of probation in the company, each of them is given a machine to operate on. In the context of training methods, this scenario best illustrates:.a) on-the-job training.
b) refresher training.
c) sensitivity training.
d) vestibule training.

The answer to the question is D: Vestibule Training

Explanation:

The word Vestibule refers to several things one of which is the lobby next to the outer door of a building. Please see attached picture showing the vestibule of a building in New York City.

Notice that the lobby or vestibule is part of the building but not on the inside. We could say near the building.

Vestibule Training which means Near-the-Job training derives from the above.

It is an approach to personnel training in which new employees, before starting their work duties, spend some time learning in a special section (vestibule), apart from the actual work environment that duplicates as precisely as possible the setting and conditions in which the employees will actually be working once their training is complete.

This should not be confused with On-the-Job training which is training provided in the workplace during regular working hours for the purpose of developing or enhancing the knowledge, skills, and abilities of employees.

During On-the-Job training, the trainees learn under supervision whilst doing the actual job.

Some of advantages of Vestibule training are:

1. It enables the workers to secure training in the best methods to work and to get rid of initial nervousness. During the Second World War II, this method was used to train a large number of workers in a short period of time. It may also be used as a preliminary to on-the job training. Duration ranges from few days to few weeks.

2. It prevents trainees to commit costly mistakes on the actual machines and or actual work environment.

Cheers!

lives by a moral and ethical code