单选题 Which classification of drugs is the most potentially fatal if the client takes an overdose?
A. Antihistamines.
B. Dopaminergics.
C. Phenothiazine antipsychotics.
D. Tricyclic antidepressants.

【正确答案】 D

【答案解析】Tricyclic antidepressants can create fatal cardiac arrhythmias. Overdose of the other medications is rarely fatal.