A paragraph structure is a way you organize your thoughts into a paragraph. It consists of 3 simple parts: The topic sentence, supporting sentence and the concluding sentence. You add lots of detail to each of these sentences, to make them look complicated.
You can add more detail to the answer yourself explaining more about each sentence.
Base on the question that is asking to complete the said statement or phrase that is in the question base on the said lines in the question and in my research and further investigation, the possible answer would be letter A. introduce. I hope you are satisfied with my answer and feel free to ask for more if you have question and further clarifications
Answer:
D
a star with three planets and their many moons orbiting it