Final answer:
Light sedation is characterized by the ability to respond to verbal instructions and maintain the airway independently; it does not involve the loss of protective reflexes or unresponsiveness to tactile stimulation.
Step-by-step explanation:
Light sedation is characterized by a purposeful response to verbal stimulation, meaning that the individual can still respond when spoken to, although they may be in a relaxed state. Importantly, during light sedation, patients are able to maintain their own airway without intervention, which is aligned with option b), and they do not lose their protective reflexes, which means that option c) is not characteristic of light sedation. Unresponsiveness to tactile stimulation, as mentioned in option d), describes a deeper level of sedation or anesthesia, not light sedation. General anesthetics typically induce a reversible state of unconsciousness and immobility, distinct from the light sedation state.