Which of the following is considered a digital identifier?

A cookie ID is indeed considered a digital identifier because it is a unique string of data assigned to a user's device when they visit a website. This identifier allows websites to recognize returning users and track their online behaviors, preferences, and interactions across different sessions. Cookie IDs are essential in digital advertising and analytics, helping marketers gather insights about consumer activities without revealing personal information directly.

In contrast, options such as Social Security Numbers, home addresses, and phone numbers are typically considered personally identifiable information (PII). While they can be used to identify individuals, they do not function in the same way as digital identifiers like cookie IDs, which are specifically designed for online tracking and engagement in the digital environment.