Which variable is more difficult to isolate in a family study compared to an adoption study

A)  sex differences
B)  socioeconomic status 
C)  genetic predisposition
D)  shared environment

Socioeconomic Status

An individual's or group's social and economic position relative to others, based on income, education, and occupation.

Adoption Study

A research method in psychology that compares the similarities between adopted children and their adoptive and biological parents to understand genetic and environmental influences.

Shared Environment

Aspects of an individual's environment that are experienced in common with others, such as family living conditions, which can influence their development.