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: Dental
Triad of factors determining the severity of malocclusion include: 
Select and explain. 
A. Duration, Intensity and Frequency, B. Activity, Duration and Frequency, C. Frequency, Activity and Intensity, D. None of the above
A: Duration, Intensity and Frequency
Answer: A: Duration, Intensity and Frequency 
Explanation: The effects of any habit depends upon three factors:

Intensity - it is the vigor with which the habit is performed.
Duration - it is the amount of time spent on the habit.
Frequency - it is the number of times the habit is activated in a day.

Above-mentioned triad has direct cause-effect relationship with the habit.