Answer:
By the time of reaction and the number of receptors involved.
Explanation:
Hearing, seeing and feeling are different sensations/skills which involves different sensors. Hearing and feeling involves ears and skin neurons, while seeing requires eyes. To drive we need mostly seeing and, to a less extent, hearing.
By feeling we do not get much distraction, unless something in the car interacts with the driver. However, it would not disable the other two senses (except when something uncommon, like a push).
By listening we actually get the spatial information that we do not receive by our eyes, so, the distractions could actually help our driving skills and reduce somehow the risk of accidents. And it does not impede seeing.
Finally, seeing is the most important while driving. We cannot drive without eyes. Also, the reaction time of the human to events is about 1 second and the probability of having an accident depends on the reaction time of the driver to a possible event. So, if there is a distraction whatsoever it would mean that the time to react to an unexpected thing would be increased with the time that the distraction gets attention, increasing even more the probability of an accident.
