The text appears to discuss the impact of visuals in a presentation, emphasizing their role in enhancing the key messages and supporting the overall delivery of the speech. The surrounding context suggests that there's a focus on how the choice of visual elements—such as images, graphs, or videos—can influence the audience's understanding and retention of the information presented.
To complete the sentence, the second word should relate to the function that visuals serve in the context of a speech. Given the choices “style,” “replacing,” and “content,” the most fitting word would be “content.” This implies that visuals are strategically used to reinforce or clarify the main ideas of the speech, thereby improving the audience's grasp of the subject matter.
So the completed sentence would read: “Carefully chosen visuals can affect a presentation by highlighting important points and supporting the content of the speech.”