Robertson's Milling is having a difficult time finding employees to work in its machine shop operations. TSTC has been a good source of trained technicians, but the company still cannot keep up with completing its orders on time. As a result, Robertson's Milling has entered into a contract with another company $($ARCO Inc.$)$ to complete some of the primary work on projects and then turn the work back to Robertson's for final completion.

This is called

subsourcing

transferization

outproviding

outsourcing