To ensure that an **interior rearview mirror** is properly adjusted, it is essential that the driver can see **all sides of the rear window**. This ensures complete visibility of what is happening behind the vehicle, which is crucial for driving safety.

- Rearview mirrors are tools that allow the driver to observe what is happening on the sides and behind the vehicle.
- In the case of the interior rearview mirror, it is important that it is adjusted so that all four edges of the rear window can be clearly seen. This provides a complete and unobstructed view of the rear area.
- If the interior rearview mirror is not properly adjusted, it is necessary to stop the vehicle in a safe place and make the necessary adjustments to ensure optimal visibility.

Correctly adjusting the interior rearview mirror is a fundamental part of preparation before starting to drive, along with other adjustments such as the seat and seatbelt.