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: ENT
In Chevallet fracture of nasal bone, the mechanism of trauma is -a) Blow from sideb) Blow from below c) Blow directly from front d) Any of the above 
Select and explain. 
A. ab, B. a, C. ad, D. bc
A: ab
Answer: A: ab 
Explanation: None