In an electromagnetic wave, at an instant and at a particular position, the electric field is along the negative \( z \)-axis and magnetic field is along the positive \( x \)-axis. Then the direction of propagation of electromagnetic wave is :
at \( 45^{\circ} \) angle from positive \( y \)-axis
positive \( z \)-axis
positive \( y \)-axis
negative \( y \)-axis
