The Observed Characteristics of a Quasar Are

The observed characteristics of a quasar are:

A) a diffuse circular image, no redshift of the spectrum, and often a very bright radio source.
B) a starlike image, with a highly variable Doppler spectrum that shifts from red to blue, and often a very bright radio source.
C) a starlike image, a highly redshifted spectrum, and often an intense radio emitter.
D) a starlike image, an extremely blueshifted spectrum, and often an intense radio emitter.