A psychologist obtains a random sample of 22 mothers in the first trimester of their pregnancy. The mothers are asked to play classical music in the house for at least 30 minutes each day until they give birth. What is the purpose of this study?
1) To determine the effect of classical music on the development of the fetus
2) To investigate the relationship between classical music and maternal stress levels
3) To examine the impact of classical music on the mother's emotional well-being
4) To explore the connection between classical music and the baby's sleep patterns