Answer the following question given this paragraph:   the history of galactic evolution has been, and the nature of space in their vicinity. However, so many black holes are now known that correlations between black hole mass and galactic nuclei characteristics are being studied. What is the mechanism for the energy output of quasars? These distant and extraordinarily energetic objects now seem to be early stages of galactic evolution with a supermassive black-hole-devouring material. Connections are now being made with galaxies having energetic cores, and there is evidence consistent with less consuming, supermassive black holes at the center of older galaxies. New instruments are allowing us to see deeper into our own galaxy for evidence of our own massive black hole.   Q: What distant and extraordinarily energetic objects now seem to be early stages of galactic evolution with a supermassive black-hole-devouring material?   A:


 - pulsars;
 - stars;
 - neutrinos;
 - quasars;
The answer is:
quasars