The correct answer is letter D
According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), this is a disorder characterized by excessive worry or apprehensive expectation.
Studies show that the disorder is linked to neurotransmitters that give the brain a feeling of well-being and happiness, such as serotonin, dopamine and norepinephrine. But not only that. Genetic factors, quality of life, diet and stress routine are also related to the development of anxiety.