**Core Concept**
Perinatal mortality refers to the death of a fetus or newborn during the perinatal period, which is the last month of pregnancy to the first week after birth. The causes of perinatal mortality are multifactorial and can be attributed to various maternal, fetal, and environmental factors.

**Why the Correct Answer is Right**
The most common causes of perinatal mortality include fetal growth restriction (FGR) due to placental insufficiency, preterm birth, and congenital anomalies. Fetal growth restriction occurs when the placenta fails to provide adequate oxygen and nutrients to the fetus, leading to intrauterine growth restriction. Preterm birth is a leading cause of perinatal mortality, as premature infants are more susceptible to respiratory distress syndrome, infections, and other complications. Congenital anomalies, such as heart defects and neural tube defects, can also contribute to perinatal mortality.

**Why Each Wrong Option is Incorrect**
**Option A:** **Placenta previa** is a condition where the placenta partially or completely covers the cervix, leading to bleeding during pregnancy. While placenta previa can cause significant maternal and fetal morbidity, it is not a common cause of perinatal mortality.
**Option B:** **Maternal hypertension** can lead to complications such as preeclampsia and fetal growth restriction, but it is not a direct cause of perinatal mortality.
**Option C:** **Intrauterine infection** can cause fetal demise, but it is not a leading cause of perinatal mortality compared to other factors.

**Clinical Pearl / High-Yield Fact**
Remember the "3 Ps" of perinatal mortality: **Preterm birth**, **Placental insufficiency**, and **Congenital anomalies**. These factors are the most common causes of perinatal mortality and should be considered in the differential diagnosis of fetal or neonatal death.

**Correct Answer:** D.