It Is Theorized That a Pulsar Only Emits X-Rays and Visible

Multiple Choice

It is theorized that a pulsar only emits X-rays and visible light during its early history.What do you suppose is the basis of this theory?

A) As the pulsar's energy dissipates,the frequency of the energy it emits drops.
B) X-rays are likely the result of radioactive decay,which only can occur in a pulsar's early history.
C) X-rays and visible light are both part of the electromagnetic spectrum.
D) The pulsars high rate of spin produces a magnetic field that,over time,slows the pulsar down.