What Happens to Active Galaxies When Their AGNs Run Out

Multiple Choice

What happens to active galaxies when their AGNs run out of fuel?

A) The black holes powering them collapse even further.
B) They simply become normal galaxies.
C) They slowly dissipate into clouds of gas and dust.
D) They eventually pull in material from farther out, starting the AGN process all over again.
E) They explode as gamma-ray bursts.