In Factual Argumentation, Presumption

In factual argumentation, presumption

A) resides with the advocate and is natural when the proposition is treated as a hypothesis to be tested when we use argumentation to seek knowledge.
B) resides with the opponent and is natural when the proposition is treated as a hypothesis to be tested when we use argumentation to seek knowledge.
C) resides with the advocate abd is artificial when the proposition is treated as a hypothesis to be tested when we use argumentation to seek knowledge.
D) resides with the opponent and is artificial when the proposition is treated as a hypothesis to be tested when we use argumentation to seek knowledge.