题目

In tough economic times, school counselors (顾问) don’t just wait for students to come to their offices in search of college brochures, health pamphlets or other help. These days, they are looking for at-risk kids to prevent personal or academic troubles before they arise. Nowadays, students and families need the guidance more than ever. Counselors play a steadying role in schools as the economy weighs on families, college admission becomes even more competitive, immigration continues to reshape the population and state-testing pressures many students. They use computers to search through 一个物体正在做加速直线运动如图，正确的图象是（　　）A．B．C．D．