This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: ECG and Arrhythmias 1, Subject name: Medicine
Normal Axis of the hea is best described as being between: 
Select and explain. 
A. -30 to + 110, B. +30 to - 110, C. -30 to - 110, D. +90 to + 110
A: -30 to + 110
Answer: A: -30 to + 110 
Explanation: Cardiac Axis Normal Cardiac Axis Normal cardiac axis flow down and towards the left lower aspect of the hea between - 30 and +110 Left Axis Detion Cardiac axis flow is upward and toward the left upper half of the hea between -30 and -90 Right Axis Detion Cardiac axis flow is downward and toward the right pa of the hea between +90 and +/-180 Extreme Right Axis Detion When flow of cardiac axis is upward and to the right between +/-180 and -90