Someone or something that produces a result is a

1.cause.
2.central idea.
3.relationship.
4.signal word.

to me i think class room sitting education is better. i do online school and i have not learned a think haha. when i sit in the classroom i just sit there and kind of pay attention but still i get so far ahead in the class when im doing online i have nothing else better to do but play video games and i sit in school and learn and have friends and just actually learn. when i'm doing online i sit here listing to music and get on and and look up the answers i guess that is my fault for being a cheater. but to be honest i think sitting in the classroom is better.