A sinusoidal electromagnetic plane wave travels through the empty space in $x$ - direction. The electric wave is polarized in the $y$ - direction frequency of waves is $1.5\: GHz$. At a certain point $P$ in space, the oscillating $E_y$ attains a maximum magnitude $E_o = 6.3 \: V/m$ \[\] The direction of magnetic field vector is along?

Question

$\begin {array} {1 1} (a)\;x - axis & \quad (b)\;y - axis \\ (c)\;z - axis & \quad (d)\;y \: and \: x\: axis \end {array}$