Source options is used to deliver ads based on the "Site-Source" Targeting.
For example in banner delivery limitation, set limitation "Site-Source" and set any value. For example : schools. And while generating invocation tags if we ad "source" as "school", only that particular ads will deliver on that.
If you are running several ads and wants to deliver ads based on the source targeting and then you can use this option. Otherwise leave it as empty.
