Nauseated means sick at the stomach. Nauseous means sickening to contemplate. The correct word is preventive . Proved is the past participle of prove . Proven should be used as an adjective only.
Quotation is a noun.
Quote is a verb. Quote may also be used as a noun in the colloquial or informal usage of the word. This usage would be acceptable, for example, in dialogue. When you rebut a statement, you contradict or deny it, but that does not mean you have done so successfully. When you refute a statement, you conclusively prove that you are correct.