Why was modern classification invented?
a: traditional classification could not classify all living things.
b: scientists realized related organisms do not share similar characteristics.
c: scientists understood that species share a common ancestor.
d: modern classification is faster and easier to use.

The modern classification was invented because the scientists understood that species share a common ancestor. The correct answer will be C. 

I believe the answer is: C. Scientists understood that species share a common ancestor. 

Prior to modern classifications, Organisms are only divided into three kingdom, Bacteria, Archaea, and Eukarya

Because scientists understood that all of these organisms share a common ancestor, there is a need to categorize each organisms into a more smaller group using their specific characteristic as a basis in order to make research on each animals become easier/more focused.

Because of this, modern classification system was created.

The answer is the third one or c

1.  go out into nature and commune with the divine2.  experience real solitude to truly perceive nature3.  realize that individuals are meant to learn from nature and transcend it4.  think of nature as a symbol of the divine