When will Google Analytics be unable to identify sessions from the same user by default?

When will Google Analytics be unable to identify sessions from the same user by default?

• When the sessions happen in the same browser on the same device
• When the sessions happen in the same browser on the same day
• When the sessions share the same browser cookie
• When the sessions happen in different browsers on the same device

Correct answer is:

When the sessions happen in different browsers on the same device