Capitalism is not a system of government, but an economical system - so it can't be the correct answer.
The correct answer is" republic" - in a republic people don't exercise their power directly, but choose representatives and this is the case in the US (the representatives are for example the Congress and the President)
<span>This speaker is guilty of "attack on a person".
Argumentum ad hominem is a argumentative technique whereby a contention is countered by assaulting the character, thought process, or other characteristic of the individual making the contention, or people related with the contention, instead of assaulting the substance of the contention itself.
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