For biological evolution to occur by way of natural selection, the trait being selected for need NOT:

A. be heritable

B. very among individuals

C. increase an individuals life spand

D. increase an individuals reproductive success

The answer is c. Natural selection is when inheritable traits that they need to survive is passed down to the next generation. Biological revolution changes the environment so the organism's offspring has to change with it through genetic variations. If you increase it's life span than you may not have genetic variation over a period of time.