Claim is the starting point for an argument. Good claims must be debatable, defensible, and insight-yielding.
Counterclaim is a claim that negates or disagrees with the thesis/claim.
Data allows the audience to understand what facts exist to support the claim. For an argument to move forward, the audience must at least provisionally accept the data. It provides a safe starting point since it's rooted in fact.
There is no set way to begin an argument, although the most traditional way, and the best option from this list, is "claim". Then you provide evidence to back up that claim.
