According to the article The Nose Knows about the ability of mothers to detect the scent of their babies, in the main study reported, the feelings of the mothers toward their infants were operationally defined as:

Weiner (1992) proposed four classes of substance use, illustrating that adolescents use substances for a variety of purposes. Name and briefly describe two purposes of substance abuse

What will be an ideal response?

A researcher has identified seventy individuals with a relatively rare psychological disorder. These individuals are asked to identify blood relatives, who are contacted by the researcher to see if they have the same disorder. What kind of research study is being performed?

a. an epidemiological survey c. a historical study b. a genetic linkage study d. a correlational case study