1. "God contains all perfections, including existence. God necessarily exists": This addresses more the identity, the defining attribute, of God rather than addressing the causative principles behind the presence of God.
2. "All things are the result of earlier causes; that causal sequence had to begin, and only God could have begun it": This presents a logical fallacy since an exhaustive catalogue of the inceptions of causalities doesn't exist.
3. "Things in nature demonstrate too much complexity and design to have arisen by accident; God must exist in order to have created and designed that complexity": This is persuasive speculation based upon observable fact. Of the three, this is most plausible since it acknowledges within itself its speculative nature.
A fourth persuasive argument option favored by some is akin to the persuasive argument for the notion of romantic love, one never yet successfully refuted: "I feel something life changing, valuable and affirmative and euphoric otherwise unaccountable; therefore it must be God [or: therefore it must be love]".