What genetic factor has been cited as a cause of anxiety disorders in children?

Maximum life span is defined as the

number of years a newborn is likely to live. risk of mortality. average age at death. upper limit to which members of a species can live.

When two variables are linked and their individual effects cannot be isolated, we speak of the variables as being

a. independent variables. b. dependent variables. c. confounded variables. d. codependent variables.