You plan to create a SharePoint Business Process Automation (BPA) project.
You need to process items for approval with the least amount of developer effort.Which tool should you use?

A.
Remote Event Receiver

B.
Out-of-the-box workflow

C.
SharePoint Designer workflow

D.
Work Item Timer Job

Explanation:
Workflows in SharePoint 2013 allow you to model and automate business processes. These business
processes can be as simple as a document approval process with a single approver (shown in example below),
as complex as customer-facing product catalog using web service calls and database support, or as formidable
as virtually any structured business process, full of conditions, loops, user inputs, tasks, and custom actions.
Example: Simple SharePoint workflow

Get started with workflows in SharePoint 2013