Final answer:
The first Delta Chi convention took place in 1902 in Chicago, Illinois, serving as a significant event in the fraternity's history to promote unity among its members.
Step-by-step explanation:
The first Delta Chi convention was held in 1902 in Chicago, Illinois. This event marked a pivotal moment in the history of the fraternity, bringing members together from various chapters to discuss matters of importance to the organization and to foster a sense of unity and brotherhood among its membership. The correct answer to the question is therefore option b) 1902 in Chicago, Illinois.