Answer:
B
Step-by-step explanation:
This is because the original male is not affected by the disease. In the second generation they have a female child who is a carrier of the disease because she passes it down to her son, but she is not affected. Seeing how all males that carried the disease were affected at some point the disease must lay dormant in female carriers but not males. This means the original father cannot be a carrier of the disease. Hope this helps!