19. in an inertial frame of reference, it is found that the electric field e(7, t) and the magnetic field b(, t) are perpendicular to each other at all points i

19. In an inertial frame of reference, it is found that the electric field E(7, t) and the magnetic field B(, t) are perpendicular to each other at all points i.e., E(, t). B(, t)=0. If the fields observed in some other Lorentz frame of reference are denoted by E'(F', t) and B(F', t) (A) E ||B' at all points (B) E.B-0 at all points (C) E' B>0 at all points (D) E'.B 0 at all points