What is the main challenge astronomers face when trying to directly detect black holes?(1 point)

The main challenge astronomers face when trying to directly detect black holes is that "Black holes trap all light." This is because their immense gravitational pull prevents light from escaping, making them difficult to observe directly. Instead, astronomers often detect black holes indirectly by observing the effects of their gravity on nearby stars and gas or by detecting X-rays emitted by material falling into them.