Dr White Reads About a New Theory That States That

Multiple Choice

Dr. White reads about a new theory that states that depression is caused by increased levels of estrogen in the womb. To test this theory, she conducted a study comparing the level of estrogen in amniotic fluid in individuals who were later diagnosed with depression with the level of those who did not develop depression. Dr. White found no differences between the groups in estrogen levels in the amniotic fluid.
In this study, estrogen levels in participants were the .

A) theory
B) research question
C) hypothesis
D) data