SOC A local church has been experiencing steady growth in membership and wants to launch a membership drive. Before they begin, they would like to find out what types of people are most likely to attend services each week. A random sample of 15 existing members has been asked how many times they attended services over the past five weeks and for certain other information. Which independent variables have significant relationships with attendance?

a. Attendance by education

b. Attendance by length of residence in present community

c. Attendance by extent of television watching

d. Attendance by number of children