A source travelling towards us at (3/\(c\) emits photons in a direction perpendicular to its velocity. If the source emits photons with energy of 0.5 electron volts in its own rest frame, which of the following energies, in electron volts, do the photons have in our rest frame?

W) 0.3

X) 0.4

Y) 0.5

Z) 0.6
X) 0.4