Suppose We Randomly Selected 250 People,and on the Basis of Their

question 87

Multiple Choice

Suppose we randomly selected 250 people,and on the basis of their responses to a survey we assigned them to one of two groups: high-risk group and low-risk group.We then recorded the blood pressure for the members of each group.Such data are called:

• A)observational.
• B)experimental.
• C)matched.
• D)None of these choices.

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Definitions:

Melatonin Release

The secretion of the hormone melatonin by the pineal gland, regulating sleep-wake cycles.

Darkness

The absence of light in an environment, resulting in limited visibility.

Homeostasis

The regulation of internal conditions within an organism to maintain a stable, constant environment despite external changes.

Biological System

An organized group of organs and structures that work together to perform a specific function or task in a living organism, such as the nervous system or respiratory system.