Both parents have blood type O, but do not know if they are Rh + or -.
A. What are the chances the offspring is type A blood? _____%
B. What are the chances the offspring is type B blood? _____%
C. What are the chances the offspring is type AB blood? _____%
D. What are the chances the offspring is type O blood? _____%
An explanation would be helpful, but it's not necessary. :)