Answer:
the Echinoderms.
Explanation:
Examples of echinoderms: starfish, sea urchin, feather stars and sea cucumbers.
Some arteries carry oxygenated blood just as some capillaries do.
Some veins carry deoxygenated blood just like some capillaries do.
Answer:
Because males are never carriers for x-linked trait, only females are carriers which gives them a lower chance of receiving the trait. While males can either have the trait or not have it.
The circulatory system is the form of transport in plants and animals. Animals should have nutrients and oxygen that spread every cell in their body. Plants should have nutrients and carbon dioxide spread in their "body". Both plants and animals must also have waste product away from their systems.
Since you are trying to investigate the possible variables that contribute to reef threats, it is advisable that you do an environmental study between two reefs that have characteristics that are similar or are closely similar. With this, you will be able to identify which is the primary cause of reef threats. Thus the correct answer is B.