Although Individual Couples Show a Range of Difference in Post-Partum

Although individual couples show a range of difference in post-partum sexual desire and activity, your text discusses a study that appears to have found a variable predicting which couples would be much less likely to be having sexual relations one year after childbirth.What was this predictor variable?

A) Not being sexually active at the third month of the pregnancy.
B) Not scoring well on a measure of couples' communication about sexuality.
C) Not being able to sleep through the night for the child's first year of life.
D) Not breast feeding.