The similarities and differences between what video games can teach us and the violent side of video games

Video Games has two side, the good side and the bad side. 
It can teach us how to be cooperative. Some video games requires teamwork, cooperation and communication.
Video games helps improves our minds. Some video games helps in improving our cognitive functions.
Video games also helps us in our Decision-making skills. One micro thing can do a macro change in playing video games, as well as in our real worlds.
But aside from this, video games can also lead us to a bad side.
Most video games has themes of violence which can affect a person's behavior.
It may cause children or even adults to have a more aggressive behavior. Video games can also lead to teaching wrong values. 

But it always depends on the person involve. :) 

Hope this helped you!

A. cause and effect is the correct answer