Who is allowed to issue a certificate on the testing of a speed limiter?

The correct answer includes options 1 and 2 because, under German traffic regulations, only specific entities are authorized to issue certificates for speed limiters.

1. The vehicle manufacturer must be officially recognized to ensure that the speed limiter installed meets all safety and regulatory standards.
2. A workshop authorized by an appropriate authority can guarantee that the installation and testing are done according to legal requirements.

The third option, "All garage workshops for commercial vehicles," is not included because not all workshops have the necessary accreditation or knowledge to test speed limiters safely and correctly. Recognizing only qualified manufacturers and authorized workshops helps maintain road safety by ensuring that speed limiters function properly and comply with legal standards.