Adam Sanderson is the Human Resources director for a growing real estate management firm in the Northeast United States. In the past, Adam's company has managed payroll internally. But the company has grown significantly over the past $5$ years, and managing payroll is becoming increasingly more difficult. Additionally, the administrative burden of managing payroll internally is diverting much needed resources from more important business problems and opportunities. Executive leadership approved Adam's proposal to retain an external or outside company to fully manage the payroll. Based on Adam's research, this new arrangement with save money and lead to more efficient use of internal resources. Adam's new strategy for managing payroll is best described by which of the following terms?

Offshoring

Expatriation

Outsourcing

In$-$shoring