At an advertising agency, you add several clients to your portfolio but they’re across different categories. What’s the correct way to structure the Campaign Manager 360 instances to make sure transferability is easy and simple?

You should create several networks, with one for each of the clients.
You should create an agency account with multiple advertisers within the account.
You should create multiple campaigns for each account you work with within the agency.
You should create multiple campaigns, with one for each client.