Why we do too much for our living when we know that we are going to die?

Its a difficult too say, Y did you enter this question, if you know your going to die, THAT was an example. you see..  we have needs and wants and the points is simple. do u want to die? no. i hope not at least,s u do things to survive, like lets say u have a bow an Arrow ur Starving U see a Deer what do you do??? you shot It, cook it THEN EAT IT. use its fur to stay warm. U do what you NEED TO DO, lick get a job and have a family BECAUSE is LIFE!!!
and Natural Human Instinct. 

Thank You have A Great Day!

-Salem :3  

Answergoogle earth; i believe this is the correct answer, plz check first;

The correct answer is a)  a resource with a limited supply; it will run out.