Answer:
Procedure.
Step-by-step explanation:
A procedure can be defined as a comprehensive set of sequential steps and actions which is typically used to specify the accepted, effective and efficient method for performing a task or executing a project and plans.
This ultimately implies that, procedures are mainly used by various companies or organizations to always achieve a standardized level of output and consistency in achieving its goals and objectives.
Hence, if you want all your stores to only accept returns with receipts this would be an example of a procedure.