What Is the Best Evidence for an Extremely Massive Black

question 4

Multiple Choice

What is the best evidence for an extremely massive black hole in the center of the Milky Way?

• A)Huge amounts of X-rays are pouring out of the center of the galaxy.
• B)The center of our galaxy hosts a pulsar that is spinning so fast that it could only be a black hole.
• C)We observe stars vanishing in the center of the Galaxy as they are sucked into the black hole.
• D)The orbits of stars in the center of the galaxy indicate that the presence of 3- to 4-million-solar-mass object in a region no larger than our Solar System.

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Definitions:

Conditioning Stimulus

A previously neutral stimulus that, after association with an unconditioned stimulus, comes to trigger a conditioned response.

Learning Stimulus

Any stimulus that influences or changes learning behavior; often involved in associative learning processes where it becomes linked with a specific response or behavior.

Discriminative Operant

A discriminative operant is a behavior influenced by the presence of a specific stimulus, indicating that reinforcement or punishment is available, thus guiding the organism's responses.