D, because whether or not the rivers flow into the mediterranean has no effect on early civilization.
Governor serves a 4 years term
When dopamine levels are elevated this reward pathway reinforces the use of the drug.
Dopamine is an organic chemical that is produced in our bodies, and is related to reward-motivated behavior.
The anticipation of most types of rewards increases the levels of dopamine in the brain, and many drugs also increase dopamine as well as blocking its reuptake into the neurons follow release.
