Answer: A flowchart proof presents a logical argument using boxes and arrows.
Explanation:
We know that a flowchart proof is a way of representation of a mathematical proof that includes a logical series of statements ( or can say arguments) in boxes with connecting arrows.
i.e. we use boxes and arrows in a flow chart proof.
By the definition of flowchart proof, the complete sentence will be : A flowchart proof presents a logical argument using boxes and arrows.