The limbic system is a set of brain structures, not a separate system which is located on both sides of the thalamus and it includes structures from the telencephalon, diencephalon, and mesencephalon. This system is involved in feeling the emotions such as joy and happiness. For example, nucleus accumbens is part of the limbic system and it is involved in reward and pleasure that can make happiness.
Besides that, the precuneus (located in front of the upper portion of the occipital lobe) is involved in feeling happiness. Scientists have shown that there is a positive correlation between the volume of grey matter in the right precuneus and the subject's subjective happiness score.
Answer:
because you keep producing more and more
Explanation:
D - Enormous energy requirements
