Answer:During pregnancy, red blood cells from the unborn baby can cross into the mother's blood through the placenta. If the mother is Rh-negative, her immune system treats Rh-positive fetal cells as if they were a foreign substance. The mother's body makes antibodies against the fetal blood cells
Explanation:
An example are our arms are similar to other s
The answer is b I think that is the answer
Answer:
B
Explanation:
Valleys are created by streams of running water
