This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
A 30 year old man who was recently started on haloperidol 30mg/day developed hyperpyrexia, muscle rigidity, akinesia, mutism, sweating, tachycardia and increased blood pressure. The investigations showed increased WBC count, increased creatinine phosphokinase. There is no history of any other drug intake or any signs of infection. The most likely diagnosis - 
Select and explain. 
A. Drug overdose, B. Neuroleptic malignant syndrome, C. Drug induce Parkinsonism, D. Tardive dyskinesia
B: Neuroleptic malignant syndrome
Answer: B: Neuroleptic malignant syndrome 
Explanation: Features of neuroleptic malignant syndrome 

Marked muscular rigidity                            
High fever                                                            
Autonomic instability (↑ HR & BP, Sweating)  
Disturbed consciousness   
Catatonia & stupor
Leucocytosis     
Increased CPK   
Myoglobinemia & Myoglobinuria