Susan, the School Principal, Is Interviewing Applicants for a Position

Susan, the school principal, is interviewing applicants for a position as an elementary school teacher in an isolated rural community in northern British Columbia. Which of the following questions can she legally ask?

A) Do you have any children? This is an excellent school.
B) Are you married? It is difficult to meet single people out here, and we have had many single teachers quit.
C) Most people here are churchgoers. We find that our teachers fit better into the community if they have the same values. Would you be active in any of the churches here?
D) All of our students are native-English speakers. What language do you speak and write fluently?