Final answer:
The answer to the number of largest cities with FFA chapters, including New York, Chicago, and Philadelphia, cannot be confirmed based on the information provided. The presence of FFA chapters in large cities reflects the organization's promotion of agricultural education.
Step-by-step explanation:
The student's question pertains to FFA chapters and their presence in the largest cities. Based on the reference provided, the correct answer is not listed; thus, I am unable to confirm the correct number of the largest cities that have FFA chapters. FFA (formerly known as Future Farmers of America) is an organization that promotes agricultural education. It is important to verify the current statistics from an updated source to determine how many of the 20 largest cities have FFA chapters, including New York, Chicago, and Philadelphia.