What Measurement Gives the Closest Approximation for Divorce Rates

Multiple Choice

What measurement gives the closest approximation for divorce rates?

A) One that looks at couples who married thirty years ago and what proportion of that population had since divorced.
B) One that is calculated as the number of divorces in each year and divided by the mid-year population.
C) One based on the number of divorces in each year divided by the number of marriages in that same year.
D) One that calculates the number of people in the population ever divorced as a fraction of the population ever married.