Which of the following substance's intoxication is the cause of this patient's symptoms?
A 15-year-old boy is brought to the physician by his father because of behavioral changes during the past month. He has been failing his classes at school and staying out late at night. His father reports that the family moved to a new neighborhood 2 months ago and that the local teenagers are mall drug addicts and criminals." His pulse is 110/min, respirations are 24/min. and blood pressure is 140/85 mm Hg. Physical examination shows pupillary dilation and diaphoresis. On mental status examination, his effect is agitated, and his thought process is confused.
A. Alcohol B. Amphetamine C. Amyl nitrate D. Cannabis E. Heroin