THIS IS known as the PERICARDIUm
I'd say A: tidal waves. B, C, and D don't really seem to fit for me.
Answer:
Blood is carried away from the heart by arteries. Blood that is rich in oxygen. Blood that is low in oxygen is returned to the heart by veins. there is more pressure in arteries than in veins.
The answer is A because in the process of mitosis and meiosis chromosomes are single-stranded groups that are condensed to chromatin when the process of division of cells chromosomes replicate to make sure that the new daughter cells received the correct number of chromosomes
QUICK ANSWER
A combination of sand, salt and water is an example of a heterogeneous mixture. A heterogeneous mixture is a type of combination where the constituents of the mixture are not uniform, and there are two or more distinctive phases of separation.