The marketing team at Northern Trail Outfitters wants to send birthday discount coupons to its...

In the scenario where the marketing team at Northern Trail Outfitters wants to send birthday discount coupons to recipients and accommodate family members who share a single email address, the most appropriate attribute to use for uniquely identifying each family member is the Subscriber Key. The Subscriber Key is a unique identifier in Salesforce Marketing Cloud that allows for the differentiation of individuals even if they share the same email address.

By assigning a unique Subscriber Key to each family member, the marketing team can ensure that personalized content, such as birthday discounts, is appropriately targeted and managed for each individual, regardless of the email address being shared. This approach allows for more personalized and targeted marketing efforts, enhancing the customer experience and engagement.

References: Salesforce Marketing Cloud documentation on Subscriber Management clearly outlines the importance and use of the Subscriber Key for unique identification of subscribers in scenarios where multiple users might share the same contact information, such as an email address.