题目

阅读理解 My name is Clara. I still remember that chilly December day,sitting in science class. I'd finished a worksheet early and picked up a TIME for Kids magazine. A piece of news caught my eye: NASA was holding an essay contest to name its Mars rover(火星探测器). Before I even knew anything else about it,a single word flooded my 11-year-old mind, Curiosity. I couldn't want for the bell to ring so I could get started on my essay.That afternoon, I raced home, sat down at the computer, and typed until my fingers ached. “Curiosity is an everlasting flame that burns in everyone's mind关于洛伦兹力，以下说法中正确的是（　　）A．电荷在磁场中一定受到洛伦兹力的作用B．运动电荷在磁场中一定受到洛伦兹力的作用C．洛伦兹力的方向始终与电荷的运动方向垂直D．让磁感线垂直穿入左手手心，四指对着电荷运动，则大姆指指向就是洛伦兹力方向