Why Would Astronomers Place an X- Ray Observatory in Space

Multiple Choice

Why would astronomers place an X- ray observatory in space, like the Chandra observatory?

A) to record X- rays emitted from the big bang; the so called background radiation of the universe
B) to map deep X- ray emissions from deep space, particularly as a proxy for materials being sucked into black holes
C) to map X- ray emissions from the moon
D) to map X- ray emissions from the sun