Answer:
b, d
Explanation:
a, may be right since mutaion does benefit species in certain ways but since it's specifically saying fatal the a is not right.
b, because even though it doesn't happen often, 2 diverse species might interbreed if a survival or specific situation is given.
d, natural selection kill of those weak and helps the strongest survive by making genetic modifications throughout the generations going from one species to a completely different one in years.