This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
Wide QRS duration is- 
Select and explain. 
A. >0.8sec, B. >0.9sec Pattern), C. >.12sec, D. All the above
C: >.12sec
Answer: C: >.12sec 
Explanation: a wide qrs complex by definiton is more than 120 ms The QRS complex duration is wide (>0.12 seconds or 3 small boxes) in every lead. Causes of a widened QRS complex include right or left BBB, pacemaker, hyperkalemia, ventricular preexcitation as is seen in Wolf-Parkinson-White pattern, and a ventricular rhythm. Ref Harrison 20th edition pg 1576