Read this excerpt from A Black Hole Is NOT a Hole by Carolyn Cinami DeCristofano.

Reber had just one little problem. To explore the radio energy, he needed a radio telescope—a telescope that could detect invisible radio energy—but there was no such thing at the time. So he invented one. He built it in his backyard in Wheaton, Illinois. Late into the night, Reber probed the sky with his new telescope, using it to locate the source of the mysterious radio energy.

Reber mapped these signals from the sky and shared his findings. Astronomers followed up with new investigations and soon began reporting more signals. Over time, with better radio telescopes, they found that some radio sources appeared as paired patches, one on either side of a tiny dot. They called these sources "radio galaxies." They also discovered other, more starlike sources—intense dots of radio energy without patches. How strange. What could these quasars (short for "quasi-stellar radio sources") be? Were they related to the radio galaxies?

According to the excerpt, how did astronomers use Reber’s findings to add to the knowledge of black holes?

Astronomers improved on Reber’s radio telescope and discovered the sources of the radio energy signals he mapped.
Astronomers used Reber’s radio telescope and renamed his discoveries “radio galaxies” and “quasars.”
Astronomers improved on Reber’s radio telescope and made new discoveries to prove his findings were wrong.
Astronomers used Reber’s maps of the signals from the space to locate radio galaxies.

Question

Read this excerpt from A Black Hole Is NOT a Hole by Carolyn Cinami DeCristofano.

Reber had just one little problem. To explore the radio energy, he needed a radio telescope—a telescope that could detect invisible radio energy—but there was no such thing at the time. So he invented one. He built it in his backyard in Wheaton, Illinois. Late into the night, Reber probed the sky with his new telescope, using it to locate the source of the mysterious radio energy.

Reber mapped these signals from the sky and shared his findings. Astronomers followed up with new investigations and soon began reporting more signals. Over time, with better radio telescopes, they found that some radio sources appeared as paired patches, one on either side of a tiny dot. They called these sources "radio galaxies." They also discovered other, more starlike sources—intense dots of radio energy without patches. How strange. What could these quasars (short for "quasi-stellar radio sources") be? Were they related to the radio galaxies?

According to the excerpt, how did astronomers use Reber’s findings to add to the knowledge of black holes?

Astronomers improved on Reber’s radio telescope and discovered the sources of the radio energy signals he mapped. 
Astronomers used Reber’s radio telescope and renamed his discoveries “radio galaxies” and “quasars.” 
Astronomers improved on Reber’s radio telescope and made new discoveries to prove his findings were wrong. 
Astronomers used Reber’s maps of the signals from the space to locate radio galaxies.

TheSmartOne · Answer

Hey there! Welcome to QuestionCove!

What do you think the answer is? Which answers can you straight away cross out?

yeetimusprime21 · Answer

hi

yeetimusprime21 · Answer

i dont know

yeetimusprime21 · Answer

thats kinda the point of asking a question

TheSmartOne · Answer

Sure, let's take it one by one

So Reber made a telescope and then he shared his findings and everyone else used his stuff to find even more things what they called "radio galaxies"

TheSmartOne · Answer

Haha well I wanted to know how far you got and where you were stuck so I could be of more help, but I know what you mean

TheSmartOne · Answer

Does it say anywhere in the excerpt that they proved his findings we're wrong?

yeetimusprime21 · Answer

Wait ive got to go now be back in a bit

TheSmartOne · Answer

Sure, no worries! I'll wait until you get back

In the meantime, a few more things to help you get closer to answering your question

First, did you read anywhere that other astronomers proved his findings wrong?
Is there somewhere in the excerpt mention that they renamed certain discoveries?

Now keep in mind what the question is asking
It's asking how did the astronomers use what Reber found to add to the knowledge, that is what did they do that built upon Reber and progressed them further