A Training Class Is Being Held on How to Install

A training class is being held on how to install a new light fixture for a project. There are 2,433 light fixtures to install in the project, so all project team members will need to learn how to install the light fixture. The project manager wants to ensure that all fixtures are installed identically. In the training, participants learn how to install the fixture by following a step-by-step direction. All of the participants can now install the light fixture relatively easily and quickly. There's not much more to learn in the installation, so their learning tapers off in regard to the light fixture installation. This is an example of what type of learning curve?

A) Positively accelerating learning curve
B) Negatively accelerating learning curve
C) S-shaped learning curve
D) Plateau learning curve