The correct answer to this open question is the following.
Although there are no options attached we can say the following.
You ask us to imagine that there were several incidents in your school in the past few weeks. As you do not specify what kind of incidents you are talking about, we assume we have to invent them to answer the question.
If that is the case, the incidents were
1.- Noticeably, personal stuff has disappeared from the classrooms: bags, pens, watches, mugs, and so on.
2.- Students have reported that someone has been stealing money from their wallets and purses.
Immediate causes.
Recent lay-offs due to difficult economic situations have forced the school to reduce the surveillance service in school premises. School administration is in the process of hiring a new security company and is budgeting to change the surveillance camera system.
Long-term causes.
School administration does not have a real plan to address insecurity issues in the school premises. Administrations have not closed negotiations with the county police department to implement a well-thought plan to educate students and reinforce security practices in every school building.