An ionized gas contains both positive and negative ions . If it is subjected simultaneously to an electric field along the ` +x` - direction and a magnetic field along the ` +y` - direction and the negative ions towardws `-y` - direction
A. positive ions deflect towards +y direction and negative ions towards -y direction .
B. all ions deflect towards +y direction
C. all ions deflect towards -y direction
D. positive ions deflect towards -y direction and negative ions towards +y direction .
