In an electromagnetic wave,the electric field $\vec{E}$ and the magnetic field $\vec{B}$ oscillate in the region near the source as:

• A
  Parallel to each other and in the same phase
• B
  Perpendicular to each other and in the same phase
• C
  Parallel to each other and with a phase difference of $\pi / 2$
• D
  Perpendicular to each other and with a phase difference of $\pi / 2$