If you have active integration segments, once you move from the Contacts page to the individual contacts. You might notice that the contact is part of certain Integration lists as shown below:

You might see multiple integrations and integration segments listed under a single contact. This means, that essentially, this contact has been imported from multiple tools and is part of multiple segments/lists.

With this information, you can decide how to adjust the integration syncs or if you want to exclude contacts from a specific list.