Final answer:
Leila could most effectively add a graph to her presentation to emphasize the increase in debt due to college expenses.
Step-by-step explanation:
In order to add new value to her presentation on how an increase in college expenses affects students’ career decisions, Leila could most effectively add a graph that plots out the data in her table, emphasizing the increase in debt.
This graph would provide a visual representation of the information, making it easier for the audience to understand and analyze the data. By highlighting the increase in debt, Leila can clearly demonstrate the impact of rising college expenses on students' borrowing.