Final answer:
Mirtazapine is the medication among the provided options that is used as an appetite stimulant. It is often prescribed to patients who need to increase their weight or are dealing with anorexia.
Step-by-step explanation:
The medication used as an appetite stimulant among the options provided is B. Mirtazapine. It is an antidepressant that in addition to its use for treating depression can stimulate appetite and is occasionally prescribed for patients needing to gain weight or combat anorexia. Cyproheptadine is also known for its appetite-stimulating effects but it's primarily an antihistamine. Diazepam and Oxazepam, which are anxiolytics, do not have appetite-stimulating effects and are mainly used to treat anxiety disorders. Many psychoactive drugs manage psychiatric disorders, with specific medications being suitable for certain conditions. For instance, stimulants like methylphenidate are used for ADHD, increasing focus and alertness while decreasing appetite, which contrasts with the desired effect of an appetite stimulant. Therefore, understanding the purpose and side effects of each medication is crucial for proper treatment.