Please answer the following question: Read the article and select the best answer. Article: Going back to school is a very exciting event for my two boys. It means getting new school bags and books, and seeing friends again after the summer holiday. My oldest son, 9-year-old Salem, asked me several times where we would go to buy a backpack, while my other son, 6-year-old Abdullah, asked what school would be like this year. For the last three years, school was a nightmare for many children and their parents as violence increased and there were more attacks on schools and teachers. As a result, many parents prevented their children from going to school. One of six children in this country did not attend primary school in 2009. Many kids who did attend school were accompanied by a parent for the entire day to make sure nothing happened to their children. For poor families or those with large families, back to school can be an expensive time. The government gives some help to those living in poor neighborhoods, and school bags, note books and other items are given for free. Most of the merchants who sell notebooks and pens now sell their products out on the street instead of in stores. They sit on the ground and lay their items on the ground or they have a small table to sell their goods. The bags cost between $10 and $20, while clothes and shoes cost between $20 and $30. I found all the things I needed for my sons and even bought something for myself. I spent about $50 on each of them, including school uniforms. At the end of the day, we returned to our home carrying many shopping bags filled with items that made my children happy and excited to go back to school. I just hope this school year will be a peaceful one. Question: Many children are not going to school mainly because of _ . Options: A: the terrible education system B: security problems and poverty C: parents' distrust in schools D: the government's inability
A:
B