The flickering of an AGN allows one to calculate the size of the source. This is actually the size of the:
A)host galaxy.
B)accretion disk around the black hole.
C)event horizon of the black hole.
D)central bulge of the host galaxy.

Question

Quizplus · Accepted Answer

The flickering of an AGN, also known as variability, is caused by changes in brightness due to the accretion disk around the black hole. The size of the accretion disk can be calculated based on the time delay between changes in brightness at different wavelengths. Therefore, the size of the AGN is the accretion disk around the black hole.

The Flickering of an AGN Allows One to Calculate the Size