The smooth muscle of the ______ contracts during labor and birth.

• A. uterus
• B. vagina
• C. ovary
• D. fallopian tube

Answer: (A)

Verified step by step guidance

1. Step 1: Begin by identifying the primary function of each organ listed in the options (uterus, vagina, ovary, fallopian tube) and their roles in the female reproductive system.
2. Step 2: Recall the process of labor and birth, which involves the expulsion of the fetus from the mother's body. Consider which organ is responsible for housing the fetus during pregnancy and contracting to facilitate delivery.
3. Step 3: Understand the role of smooth muscle in the reproductive system. Smooth muscle is involuntary and contracts to perform specific functions, such as moving substances or aiding in childbirth.
4. Step 4: Focus on the uterus, which is the organ that contains smooth muscle layers (myometrium) designed to contract during labor to push the baby through the birth canal.
5. Step 5: Eliminate the other options (vagina, ovary, fallopian tube) by analyzing their functions. The vagina serves as the birth canal but does not contract to expel the fetus, the ovary produces eggs, and the fallopian tube transports eggs but is not involved in labor contractions.