The place described by the blank is visited by John's mother every Sunday. This means that the answer must be a place where she goes regularly.
Option A is incorrect. It is not specified anywhere that John's mother goes to school regularly and thus, it is incorrect.
Option B is correct. The first sentence tells us that John's mother goes to the church regularly and hence it must be the place where she goes every Sunday. Thus, church is the correct answer.
Option C is incorrect. College is incorrect for the same reasons as option A.
Option D is incorrect. Home is a place that one stays at. Some one cannot just visit their own home as they are said to be staying there. Thus, home is not a good fit.