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

In fact, every quasar and radio galaxy dot turned out to be energy from the center of an entire galaxy. Astronomers found stars careening around these centers, zooming at previously unheard-of speeds in their orbits. The motion was like an accelerating ice skater pulled around her partner in a tight twirl—or like a fish caught in a superstrong whirlpool. Something extreme had to be in the middle of each of those galaxies.

You might be able to guess what this was, but for scientists, the best answer came as a shock. In 1994 telescopic evidence confirmed the amazing cause: a supermassive black hole, with the mass not of one imploded star, not of two, but of millions—maybe even billions.

In the excerpt, the author makes a connection between the discovery of quasars and radio galaxies and

the invention of the radio telescope.
the scientist who mapped radio waves.
the identification of the Milky Way.
the confirmation of a supermassive black hole.

Read the excerpt from the code book. without much hope of a theoretical breakthrough, cryptanalysts have been forced to look for a technological innovation. if there is no obvious way to reduce the number of steps required for factoring, then cryptanalysts need a technology that will perform these steps more quickly. silicon chips will continue to get faster as the years pass, doubling in speed roughly every eighteen months, but this is not enough to make a real impact on the speed of factoring—cryptanalysts require a technology that is billions of times faster than current computers. consequently, cryptanalysts are looking toward a radically new form of computer, the quantum computer. if scientists could build a quantum computer, it would be able to perform calculations with such enormous speed that it would make a modern supercomputer look like a broken abacus. the author’s purpose in this paragraph is to convince the readers to pursue a career in analysis. explain the need for faster technology in cryptanalysis. entertain with interesting stories about supercomputers. argue for more money to develop a quantum computer.