Which of the Following Would Tend to Cause the Observed

Multiple Choice

Which of the following would tend to cause the observed earnings of women to be lower than the observed earnings of men?

A) The average woman has fewer years of schooling than the average man.
B) The average number of hours worked is smaller for women than men.
C) Women are more likely to prefer jobs that have more flexible hours.
D) All of the above would be causes.