Based on All Available Evidence, Which Conclusion About Cohabitation Is

Based on all available evidence, which conclusion about cohabitation is the most reasonable?

A) Cohabitation is the main reason why the divorce rate has risen sharply in recent decades.
B) Cohabitation is the primary cause of the rapid transmission of STDs.
C) The average age at first marriage has been increasing in part because cohabitation has become more commonplace.
D) Cohabitation only leads to lasting relationships if the couple has children.
E) Cohabitation has sharply reduced the number of domestic violence cases in America.