Placenta is the connecting link between the mother's body and the baby. It is a disc embedded in the uterine wall. This special tissue contains villi on the embryo's side of the tissue and on the mother's side are blood spaces, which surround the villi.

Placenta contains:

The correct answer is option 'C', which states that the placenta contains both chorionic villi and uterine tissue.

Explanation:

1. Chorionic Villi:
- Chorionic villi are finger-like projections that extend from the surface of the chorion, which is the outermost layer of the fetal membrane.
- These villi are richly supplied with blood vessels, allowing for the exchange of nutrients, gases, and waste products between the mother and the developing fetus.
- The chorionic villi develop from the trophoblast, which is the outer layer of cells of the blastocyst (early-stage embryo).
- The villi increase the surface area available for the exchange of substances between the maternal and fetal bloodstreams.

2. Uterine Tissue:
- The placenta is a temporary organ that develops in the uterus during pregnancy.
- It is formed by the fusion of the maternal uterine tissue and the fetal chorionic villi.
- The uterine tissue, also known as the decidua, is the lining of the uterus that undergoes significant changes to support the development of the placenta.
- The uterine tissue provides a supportive environment for the attachment and growth of the chorionic villi.
- It contains blood vessels that supply oxygen and nutrients to the developing fetus and carries away waste products.

3. Placenta:
- The placenta plays a crucial role in maintaining the pregnancy and supporting the growth and development of the fetus.
- It acts as a barrier between the maternal and fetal bloodstreams, allowing selective transfer of substances while protecting the fetus from potential harm.
- The placenta is responsible for the exchange of nutrients (such as glucose and amino acids), gases (oxygen and carbon dioxide), hormones, and waste products (such as urea) between the mother and the fetus.
- It also produces hormones, including human chorionic gonadotropin (hCG), which is responsible for maintaining the pregnancy, and progesterone, which is essential for the development of the uterus and the maintenance of pregnancy.

In conclusion:
The placenta is composed of both chorionic villi and uterine tissue. The chorionic villi arise from the trophoblast and provide a large surface area for the exchange of substances between the maternal and fetal bloodstreams. The uterine tissue, or decidua, supports the growth and attachment of the chorionic villi and provides a blood supply for the developing fetus. Together, these structures form the placenta, which is essential for the survival and development of the fetus during pregnancy.