**Core Concept**
A caesarean section is a surgical delivery method where the baby is born through incisions in the mother's abdomen and uterus. The indications for a caesarean section are divided into absolute and relative indications. Absolute indications are situations where a vaginal delivery poses a significant risk to the mother or the baby, and a caesarean section is the only safe option.

**Why the Correct Answer is Right**
The correct answer is placenta previa, a condition where the placenta partially or completely covers the cervix. This can lead to severe bleeding during pregnancy or labor, making vaginal delivery a high-risk option. In cases of placenta previa, a caesarean section is the safest option to prevent maternal and fetal complications. The placenta's abnormal implantation site can be identified on ultrasound, and a caesarean section can be planned accordingly.

**Why Each Wrong Option is Incorrect**
* **Option A:** Breech presentation is a relative indication for a caesarean section. While a breech presentation can make vaginal delivery more complicated, it is not an absolute indication for a caesarean section.
* **Option B:** Multiple pregnancy (twins, triplets, etc.) is a relative indication for a caesarean section. While the risk of complications increases with multiple pregnancies, vaginal delivery can still be a safe option in many cases.
* **Option C:** Fetal distress is a relative indication for a caesarean section. While fetal distress can be a sign of a problem that requires surgical intervention, it is not an absolute indication for a caesarean section.

**Clinical Pearl / High-Yield Fact**
Placenta previa is a condition where the placenta implants in the lower part of the uterus, covering the cervix. It is a significant risk factor for postpartum hemorrhage and is often associated with a history of uterine surgery or previous caesarean sections.

**Correct Answer: A. Placenta previa**