How should a Campaign developer restrict users from entering only one of three possible data values in a column called customerstatus?

A Campaign developer is building an automated workflow that is required to send emails to product purchasers from the previous day. The audience of each day's send must be stored in a delivery of its own.
Which type of delivery should the Campaign developer use in such a workflow?

A developer is building a campaign that selects recipients the day after recipients contact customer support and send the same email content regardless of day of execution.
A different delivery ID must be associated with each day's send for campaign analysis.
How should the Campaign developer meet the analysis requirements with the minimum daily maintenance?

If a user is to receive email notifications regarding alerts from campaign workflows, which default operator group is required?

In the picture of a workflow provided, what is the current state of workflow?