8. According to new research, patients with long COVID –long-term symptoms like brain fog, fatigue, or memory loss in the months or years following COVID-19– can exhibit a reduction in circulating levels of serotonin. Which of the following descriptions is NOT correct﹖ (A) Serotonin is a neurotransmitter. (B) Serotonin is primarily produced in the GI tract (C) Serotonin levels could be restored through treatment with Serotonin precursors Or selective serotonin reuptake inhibitors. (D) Methionine is a building block for serotonin. When methionine absorption is reduced by persistent viral inflammation, serotonin is depleted. (E) The finding could link depression with cognitive impairment in Long COVID.