There are two areas of the brain that are important parts of the reward circuit. What is the chemical that is released into the brain as a "reward"?
O Adrenaline
O Serotonin
Norepinephrine
Dopamine

B.) Serotonin I think. I may be wrong

Explanation:

option c (nickel) is not found in earth's crust. the earth's crust basically contains eight (8) elements namely: oxygen, silicon, aluminum, iron, calcium, sodium, potassium and magnesium (listed in order of abundance).

i think it's about 10 mins.

actually i think that's wrong, but i don't know how to delete this.

but who knows it might be right.