Which of These Statements Has NOT Provided Observational Evidence of the Existence

question 91

Multiple Choice

Which of these statements has NOT provided observational evidence of the existence of supermassive black holes in the centers of galaxies?

• A) The centers of these galaxies are completely dark even though it is clear that the background (the other side of the galaxy) should be bright with stars.
• B) Large amounts of energetic X-rays are being emitted from the galactic centers.
• C) Stars show very high speeds near the galactic centers.
• D) The number density of stars near the galactic center is extraordinarily high.

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Definitions:

Alimentary Canal

A series of hollow organs joined in a long, twisting tube from the mouth to the anus, through which food is digested and nutrients are absorbed.

Molluscs

Invertebrates including squids, clams, snails, and chitons; characterized by a visceral mass, a mantle, and a foot.

Visceral Mass

Internal organs of an organism; typically includes components of the digestive, reproductive, and urinary systems (if present).

Mantle

In mollusks, an extension of the body wall that covers the visceral mass and may secrete a shell.