Which of the Following Is Correct

question 110

Multiple Choice

Which of the following is correct?

• A) A continuous random variable has a probability density function but not a cumulative distribution function.
• B) A discrete random variable has a probability mass function but not a cumulative distribution function.
• C) A continuous random variable has a probability mass function, and a discrete random variable has a probability density function.
• D) A continuous random variable has a probability density function, and a discrete random variable has a probability mass function.

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Definitions:

Melatonin

A hormone produced by the pineal gland that regulates sleep and wakefulness.

Melatonin

A substance secreted by the pineal gland that controls the patterns of sleeping and waking.

Dopamine

A neurotransmitter associated with pleasure, movement, and attention in the brain.

Cortisol

Cortisol is a steroid hormone released by the adrenal glands in response to stress and has multiple functions including regulating metabolism and immune response.