**Core Concept**
Antenatal support refers to the nourishment and sustenance provided to the fetus during pregnancy. This can come in the form of umbilical cord blood, amniotic fluid, or placental transfer of essential nutrients and oxygen.

**Why the Correct Answer is Right**
Antenatal support is primarily delivered through the placenta, which acts as a vital organ for the fetus by providing oxygen, nutrients, and waste removal. The placenta develops from the trophoblast cells of the blastocyst and plays a crucial role in fetal development. The umbilical cord connects the fetus to the placenta, facilitating the exchange of essential nutrients and waste products.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided, so we cannot evaluate its accuracy.
**Option B:** While the amniotic fluid does provide a protective environment for the fetus, it is not the primary source of antenatal support.
**Option C:** The fetus does receive oxygen and nutrients from the maternal bloodstream through the placenta, but this is not a direct form of antenatal support.

**Clinical Pearl / High-Yield Fact**
A key aspect of antenatal support is the placental transfer of oxygen and nutrients, which is mediated by the trophoblast cells. The placenta is a vital organ for fetal development, and any disruptions to placental function can have significant implications for fetal well-being.

**Correct Answer:**
(To provide a complete explanation, we need the correct answer options.)