A company is planning to adopt Media Cloud and has requirements around the relationship between...

Advertisers and agencies should be created as Accounts and contacts as Contacts, and the Party Model should be adopted to define the relationships between them.

Advertisers and agencies should be created as Accounts, with agencies listed as child Accounts to the client Accounts, with Contacts related to those.

Advertisers should be created as Accounts, and agencies should be represented by a custom field added to the Contact object. Contacts should then be assigned to the Accounts.

Advertisers and agencies should be created as Accounts, and a custom lookup field should be created to represent the client/agency relationship. Contacts should be created under the Accounts.