Niagara Falls Were Formed ________

question 85

Multiple Choice

Niagara Falls were formed ________.

• A) by humans as a result of the damming of the St. Lawrence River
• B) during Precambrian time approximately a billion years ago
• C) so long ago that the river's knickpoint is now gone
• D) after the retreat of the Pleistocene ice sheets a few thousand years ago
• E) after a series of spectacular earthquakes which are still helping the falls evolve

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Definitions:

Auditory Hallucinations

Perceptions of hearing noises or sounds, such as voices, music, or ringing, in the absence of external stimuli.

Positive Symptom

In psychology, observable behaviors or thoughts, such as hallucinations or delusions, that are present in disorders but not in healthy individuals.

Schizophrenia

A long-term mental disorder involving a breakdown in the relation between thought, emotion, and behavior, leading to faulty perception, inappropriate actions and feelings, and a withdrawal from reality.

Identical Twins

Twins originating from the division of one fertilized egg, which then develops into two individuals with the same genetic makeup.