But you're afraid to reveal it or what? She simply asked you to show proof that the traditions you believe in actually came from the apostles. That shouldn't be too difficult should it?
The Church authority comes from Christ and is recorded in the Holy Scripture by the apostles. Some traditions are of course of later origin. For example, one cannot venerate a saint who has not lived yet. Other traditions are probably from apostolic times - such as for example, iconographic traditions, -- but the evidence is gone due to vandalism and passage of time. In either case the Church uses her authority throughout history to propose things for our salvation, for example, by establishing liturgical norms and canons.