原题　一束持续电子流在电场力作用下做匀加速直线运动，则在其周围空间Ａ．产生稳定的磁场Ｂ．产生变化的磁场Ｃ．所产生的磁场又可产生电场Ｄ．产生的磁场和电场形成电磁波此题考查的是麦斯韦的电磁理论．麦氏电磁理论有两个中心思想：一是变化的电场能产生磁场；二是变化的 The original subject of a bunch of continuous electron flow under the action of the electric field force to do uniform acceleration linear movement, then in its surrounding space A. Generate a stable magnetic field B. Produce a changing magnetic field C. The generated magnetic field can generate an electric field D. The resulting magnetic and electric fields form electromagnetic waves. This question is examined by Maxwell’s electromagnetic theory. Maxwell’s electromagnetic theory has two central ideas: one is that a changing electric field can generate magnetic fields; the other is changing.