Which Data Suggest the Strongest Link Between Heredity and Intelligence

question 67

Multiple Choice

Which data suggest the strongest link between heredity and intelligence?

• A) Identical twins whose IQ scores correlate at the +.9 level
• B) Fraternal twins whose IQ scores correlate at the +.9 level
• C) Biological siblings whose IQ scores correlate at the +.9 level
• D) Adoptive siblings whose IQ scores correlate at the +.9 level

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Definitions:

Sigma Notation

A symbolic method used in mathematics to denote the sum of a series of terms.

Arithmetic Sequence

A sequence of numbers in which the difference between consecutive numbers is constant.

Nth Partial Sum

The sum of the first n terms of a sequence, used to determine the cumulative value of a series up to a specified number of terms.

Geometric Sequence

An ordered list of numbers where, starting with the second term, each entry is the result of multiplying the one before it by a consistent, non-zero factor termed the common ratio.