Answer: c. Cleaning up the data.
Step-by-step explanation:
Cleaning up data in regards to Customer Relationship Management (CRM) refers to making changes to the messages sent to customers such that they are different or at the very least offer some new information that the customer has not seen before.
It is very important to do this because people do not like receiving the same messages over and over again as this could be considered spamming. This would lead to them unsubscribing from the service.