Final answer:
The manifestations of serotonin syndrome from the provided options include hyperthermia, agitation, and tremors. This condition is a risk when combining St. John's Wort with fluoxetine, an SSRI that increases serotonin levels in the central nervous system.
Step-by-step explanation:
The concurrent use of St. John's Wort and fluoxetine, a type of Selective Serotonin Reuptake Inhibitor (SSRI), can indeed increase the risk of serotonin syndrome, which is a potentially life-threatening condition. Serotonin syndrome manifests through a variety of symptoms, which can range from mild to severe. The correct manifestations of serotonin syndrome from the given options are Option 2: B) Hyperthermia, Agitation, and Tremors. This condition occurs when there is an accumulation of too much serotonin in the body, leading to overstimulation of the central nervous system. Serotonin syndrome symptoms can also include other effects like diarrhea, headache, sweating, dilated pupils, and rapid heart rate, which are not included within the provided choices.