A researcher asked a sample of dual career families about the percentage of the family budget ...

A researcher asked a sample of dual career families about the percentage of the family budget contributed by the wife's job (Y) and the total number of children (X). Pearson's r for this relationship is -0.34 . Which of the following is an appropriate interpretation of these results?
 
  a. For every dollar contributed by the wife, the number of children increases by .34
  b. For every additional child, the wife must work longer hours
  c. Every additional child lowers the economic wellbeing of the family
  d. As number of children increase, the percentage of the budget contributed by the wife decreases