The keys to a successful argumentative research essay are a clear, focused thesis on a topic supported by reasoning, and credible research in which the is considered.

controversial ; claim

Explanation:

An argumentative writing or an essay is defined as a special type of writing where an individual selects a controversial topics for the writing and then he or she does extensive research on the topics and collects facts and evidences in their research in order to establish their position or opinion on the topic so that they can prove the topic to be true or false for what they claim for. They should used explanations and evidences in support of their claims made.

c: in the east might be the correct answer