Why do authors use tension in a story?

Which best expresses the irony present in this passage?

Choose the best selection to complete the following sentence. my gave me a fantastic birthday present. a. mom’s sister c. relation b. family member d. aunt

Read the paragraph. in fact, teenagers contribute a great deal to their community. this is another reason why they must be taken into account when public policy is debated. over eighty percent of teens spend time volunteering at their schools and other organizations. this is an example of statistical analysis layering point of view outlining