Answer: C) Catch their interest early with a powerful opening.
Explanation: When writing a persuasive essay or giving a speech it is important to engage the audience (readers, listeners, etc), there are many ways to do that, for example: asking a question, telling a story, using visual elements, etc. From the given options, the one that expresses the most effective way to engage an audience is the corresponding to option C: Catch their interest early with a powerful opening.