Every day in China, about 200 million children go to school. Many of them take school buses. What should we do to keep these students safe on the road? On April 5, 2012,the State Council  published new rules about school bus safety. These new rules are stricter than the old ones. Under the new rules, local governments must make sure that students go to nearby school or _ schools to reduce traffic risks . Also, local governments must help kids in the countryside reach their school buses. From now on, school buses have a speed limit of 80 km/h on highways and 60 km/h on normal roads. While on the road, other cars must let school buses go first. The new rules also say that school buses must never be overloaded  . There are many other rules as well. A school bus must have more than seven seats. On each bus, there must be at least one adult to keep an eye on the kids. Each school bus must have a fire extinguisher  , a first aid kit   and a GPS. A series of school bus accidents happened in China in 2011. To stop such accidents, the Central Government decided to strengthen   the rules for school buses. The most serious accident happened in Gansu in November,2011. When a nine-seat minibus crashed. There were more than 60 children inside, and 21 of them died. I hope such terrible things won't happen again and all of us can pay more attention to the safety of the students. According to the passage, the government made new rules because  _  .
21 students died in school bus accidents in 2011 School buses in China were not safe enough before 200 million children in China go to school by bus every day the government encourages all students to take school buses