In order to determine the effect companion animals might have on the moods of elderly people living alone experimenters created six groups from a large population of single people over 70 years old. they had three groups: those
without pets, those who owned a dog, and those who owned a cat. they randomly selected 50 men
from each of those groups and 50 women from each of those groups for a total of 300 participants.
which of the following statements about this study is correct?