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: Pathology
The best example of a proto-oncogene activated by point mutation is - 
Select and explain. 
A. Ras, B. N-myc, C. L-myc, D. Abl
A: Ras
Answer: A: Ras 
Explanation: None