Answer: One effect that parallelism has on a written work is that C. it emphasizes ideas.
Explanation: Parallelism is a literary device that is used in many literary genres, even though is mainly used in poetry. Writers usually resort to parallelism to convey one of its most important effects, which is emphasizing ideas. As parallelism is based on repetition, it has the power to highlight the importance of certain concepts and to make the readers remember the ideas presented easily.