**Core Concept**
A classical caesarean section involves a vertical incision in the upper segment of the uterus, which is typically reserved for specific situations due to its higher risks and complications. This procedure is usually performed in emergency situations or when a previous uterine surgery has compromised the lower segment of the uterus.

**Why the Correct Answer is Right**
A classical caesarean section is often considered when there is a history of multiple uterine surgeries, leading to a weakened lower uterine segment, which increases the risk of rupture during labor. Another indication is a previous classical caesarean section, as this can lead to a higher risk of complications in subsequent surgeries. The procedure may also be considered in cases of placenta accreta or other conditions where a vertical incision is necessary.

**Why Each Wrong Option is Incorrect**
**Option A:** **Fetal distress** is not an absolute indication for a classical caesarean section. In fact, a classical section may delay delivery, potentially worsening fetal outcomes.

**Option B:** **Placenta previa** can be managed with a low-transverse caesarean section, which is a safer option than a classical section.

**Option C:** **Uterine anomalies**, such as a bicornuate uterus, may require a classical section due to the abnormal uterine shape and increased risk of rupture.

**Clinical Pearl / High-Yield Fact**
A classical caesarean section is associated with a higher risk of complications, including hemorrhage, infection, and adhesions, making it a last-resort option in obstetric care.

**Correct Answer:** B. Placenta previa can be managed with a low-transverse caesarean section, which is a safer option than a classical section.