Answer:
D.negative z direction.
Step-by-step explanation:
Hello,
In this case, electromagnetic waves are waves that result when vibrations between an electric field and a magnetic field are exhibited, it means they are composed by both oscillating magnetic and electric fields. In such a way, when the electromagnetic wave is moving across the x-direction, the associated magnetic field oscillates across the xz-plane and the corresponding electric field across the xy-plane.
In this manner, the referred electromagnetic wave is transferring energy across the negative y direction, in addition, the magnetic field turns out positive across the x direction. Considering the aforesaid reasons, one concludes that the electric field at that point and instant is in the negative z direction.
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