Which of the these elements of equipments or vehicle construction has a significant effect on safety during braking?

In the photo you can see a close-up of a car wheel - an alloy rim and a tyre, that is, the part that transfers the braking force to the road. Of the systems listed, the ABS system has a significant effect on safety during braking - answer C. Cruise control (B) keeps a set speed and does not brake in an emergency by itself, and "the AWS system" (A) is not a braking system of a passenger car.

ABS is a system that prevents the wheels from locking during braking: sensors measure the rotational speed of each wheel, and when one of them starts to lock, the control unit reduces the pressure in its brake for a fraction of a second and then immediately restores it - as many as a dozen or more times per second. A locked wheel slides over the surface and does not respond to turning the steering wheel, while a rolling one lets you steer around an obstacle while braking. On dry asphalt ABS does not shorten the braking distance much, but on a wet or slippery surface it lets you keep steering control and usually also stop sooner. In a car with ABS you brake hard and fully in an emergency, without pumping the pedal - the pulsing under your foot is the normal operation of the system, not a fault.