Final answer:
To import leads and contacts to a campaign, a user usually needs Edit access to Campaign and possibly an explicit Import Leads and Contacts permission. View All Data permission would allow importing but is excessively broad and not a minimal requirement.
Step-by-step explanation:
In order to import leads and contacts to a campaign, a user must typically have certain permissions set within their Customer Relationship Management (CRM) system, such as Salesforce. These permissions can vary depending on the specific CRM's security model, but generally, a user would require Edit access to Campaign. This allows the user to make changes to the campaign, including adding leads and contacts.
Additionally, there might be a specific Import Leads and Contacts permission that is required. In some CRM systems, this can be a separate permission that needs to be granted explicitly. Lastly, although View All Data permission would definitely allow a user to import leads and contacts as it provides extensive access rights, it is typically not a minimal requirement for this function because it allows access to all records in the system, which might not be necessary or secure for every user's role.