One Object That Is Believed to Be a Black Hole

question 5

Multiple Choice

One object that is believed to be a black hole in our Galaxy is

• A) the central star in the Ring Nebula in Lyra.
• B) the central star in the Crab Nebula.
• C) the undetected tenth planet in our solar system,whose presence has been inferred from its gravitational influence on the outer planets.
• D) Cygnus X-1,a powerful X-ray source.