What is the function of a claim in an argument?

to introduce the topic
to state the writer's opinion
to state a reason for the writer's belief
to give evidence supporting the writer's belie

The function of a claim in an argument is to state the writer's opinion or position on the topic being discussed. It is a statement that asserts a belief or proposition. While a claim can also be supported by reasons and evidence, its primary role is to present the writer's main argument or viewpoint.