What component should be discussed with a financial services customer who needs separate subscriber attributes using the same email address?

The Subscriber Key is the correct component to discuss when dealing with a financial services customer who requires separate subscriber attributes while using the same email address. The Subscriber Key serves as a unique identifier for each subscriber in a marketing platform. This means that even if multiple subscribers share the same email address, each can still be distinguished by their unique Subscriber Key.

This functionality is particularly important for businesses that have multiple accounts or records associated with a single email address. By assigning different Subscriber Keys to these records, the system can maintain unique attributes and preferences for each subscriber, ensuring that communications and data management are handled correctly.

In contrast, Contact ID typically refers to a unique identifier assigned at a different level, often not providing the necessary granularity for multiple subscribers sharing an email address. Data Extensions are used to store records and can include Subscriber Keys, but they do not inherently address the need for distinct identifiers. Lastly, a Member Record usually pertains to specific data relevant to memberships or memberships within programs, which may not directly relate to managing attributes of subscribers sharing an email address.

Thus, focusing on the Subscriber Key allows the company to effectively manage and segregate subscriber data in a way that meets the client's specific needs.