Which word could best describe the act of supporting an argument with additional information?

The word that best describes the act of supporting an argument with additional information is "contribute." This term directly indicates the act of adding valuable material or insights to bolster an argument or viewpoint. In the context of argumentative writing or speaking, contributing means providing evidence, examples, or further explanations that enhance understanding and reinforce the main claim being made. This act of reinforcement is essential for making a persuasive case and engaging the audience effectively.

In contrast, "contrast" involves highlighting differences, which does not support an argument but rather provides a comparison that can weaken or create alternatives to the original position. "Suggest" implies a recommendation or idea without necessarily providing supportive evidence, and "imply" conveys a more subtle or indirect message that does not involve direct support of an argument. Thus, "contribute" most accurately captures the essence of augmenting an argument with additional information.