A uniform magnetic field lies in the positive x - direction. An electron moving in the negative y - direction enters the region of the magnetic field. Which of the following statements is true about the direction of motion of the electron?

• A.Electron moves in a circle whose plane is parallel to the x - y plane
• B.Electron moves in a circle whose plane is parallel to the y - z plane
• C.Electron moves faster in the negative y -direction
• D.Electron changes direction and begins to move in the positive x - direction.