I believe it's oxygenated or oxygen rich blood away from the heart.
Our genes can be affected by the environment and change the way our traits are displayed, called the phenotype. However, changes in phenotype have an underlying genotypic source. Epigenetics or epigenetic changes are changes in the way traits are expressed as an effect of the environment (i.e. food we ate, chemicals in the body, environmental stresses), without changes in the DNA. Simply put, in epigenetics, some parts of the DNA are turned on or off in response to environmental conditions.
Answer:
Nuclear energy can be used and controlled and it is more efficient than other forms. I would say B.