Jenna and Lisa met for coffee. Jenna told Lisa that she is having major marital difficulties and that she is considering a divorce. Lisa responded by telling Jenna
about a rough patch she went through last year, and that she actually had filed for
divorce before working things out with her husband. This demonstrates what key
principle of the Social Penetration Theory

Breadth of self disclosure
Liberal nature of self disclosure
Reciprocal nature of self disclosure
All of the above