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
Normal female, whose father was color blind married a normal man. What are the chances of color blindness in son ? 
Select and explain. 
A. 25%, B. 50%, C. 75%, D. No chance
B: 50%
Answer: B: 50% 
Explanation: Ans. is'b' i.e., 50%