A hypothesis is a theory yet to be tested, or a "guess" that will be the basis of your excitement.
Answer:
A
Explanation:
Cardiovascular diseases involves the heart.
Any of the above options with regards to blood (etc, white blood cells, red blood cells) are related to circulatory system, not affecting the function of the heart.
Stem cells performing apoptosis to remove old cells is a myth. Stem cells can only differentiate to form cells of the same lineage, not causing other cells to undergo apoptosis. The only external factor that can cause cells to undergo apoptosis is a type lymphocyte in the immune system
Answer:
D. The oldest rock is found in the bottom layer of a rock formation.
Explanation:
