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: Unknown
3-4 months baby with heart rate 250/min, QRS complex less than 0.07 sec and no P wave, Diagnosis will be : 
Select and explain. 
A. SVT, B. Sinus tachycardia, C. PSVT with block, D. VT
A: SVT
Answer: A: SVT 
Explanation: SVTs are the most common symptomatic arrhythmias in all children including neonates.
SVTs usually have
Rate > 200 beats/minute
Normal or narrow (<0.07 sec, A wide QRS > 0.07 sec favors diagnosis of ventricular tachycardia).
Ventricular complexes on the surface ECG.