What is required for the ABS light regarding its attachment?

The requirement for the ABS (Anti-lock Braking System) light emphasizes that it must be securely attached and clean. This is crucial because the ABS light serves an important function in the vehicle's braking system. A securely attached light ensures that it will operate effectively when the vehicle is in use, providing reliable feedback to the driver about the status of the ABS. If the light is not securely attached, it could malfunction, fail to illuminate when necessary, or give false warnings, leading to potential safety issues.

Moreover, cleanliness is important because dirt or debris could obscure the light, making it difficult for the driver to see whether the ABS system is functioning correctly. This could hinder the driver's ability to react promptly to braking system warnings, which could compromise safety.

The other options do not align with safety standards and best practices for vehicle maintenance. For instance, a loosely attached light would not provide reliable information, and a cracked light could impede visibility further, not posing as a viable option. Additionally, the ABS light is a critical component of vehicle safety systems and should always be present to inform the driver about the braking system's operational status.