Final answer:
Reality orientation can be used with a client who is mildly confused to help them maintain awareness of their environment, but hypnosis, which relies on the power of suggestion, might be more effective for those who are highly suggestible.
Step-by-step explanation:
Among the techniques that can be used with a client who is mildly confused, Reality orientation (A) is one approach. This technique involves continually orienting the person to time, place, and person in order to maintain or regain their awareness of their surroundings and situation. It's often used in care settings to assist individuals with mild cognitive impairments.
On the other hand, the technique which is most effective in individuals that are very open to the power of suggestion is hypnosis (A). Hypnosis can be used therapeutically to alter perceptions, sensations, feelings, thoughts, or behaviors. However, the key factor is the individual's openness to the power of suggestion, as not all individuals will respond to hypnosis.