Evidence to support your credibility and claim. Your claim of the essay is nothing without evidence in body paragraphs
The serotonin is a chemical neurotransmitter in the brain responses to keep the "happy mood" in humans, so-called, the "the molecule of happiness". Low levels of serotonin may produce serious problems like depression, anxiety, memory low-self esteem, irritation and so on. When a lover has a low serotonin level in his brain, his mood and general behavior can be affected in great ways. Young people may not be aware of the great-negative consequences of the decreased levels of serotonin and a treatment should be carry out. Depression and anxiety can lead to terrible outcomes in someone's life.
The answer is D). He is excited at the prospect of becoming king but also fearful about what role he will have to play in making it happen.
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