Short-Period Comets, Such as Halley's Comet, Are Believed to Come

question 53

Multiple Choice

Short-period comets, such as Halley's comet, are believed to come from ______________.

• A) the Kuiper Belt
• B) the Oort cloud
• C) the asteroid belt
• D) Earth

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Definitions:

Neurotransmitter

Chemical substances in the brain that transmit signals from one neuron to another.

Serotonin

A neurotransmitter that plays a key role in mood regulation, affecting emotions, and the overall sense of well-being.

Obsessive-Compulsive Disorder (OCD)

A mental disorder characterized by unwanted and intrusive thoughts (obsessions) and repetitive behaviors or mental acts (compulsions) that an individual feels driven to perform.

Checking Routines

Behaviors commonly associated with OCD, involving repeated checking to alleviate anxiety related to fears of harm or mistakes.