Smiling When Happy Seems to Be an Expression Common to All

question 58

Multiple Choice

Smiling when happy seems to be an expression common to all human societies, suggesting that this behavior is probably

• A) based on social standing.
• B) genetic in origin.
• C) altruistic.
• D) learned.

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Definitions:

Matched Pairs

A statistical technique that involves comparing two samples that are closely related or paired, often used in before-and-after studies.

Null Hypothesis

A hypothesis in statistical tests that assumes no effect or no difference between groups or conditions being compared.

Consecutive Weeks

A succession of weeks that occur consecutively without any breaks.

Confidence Interval

A variety of values, based on statistics from a sample, which is conjectured to envelop an obscure population parameter.