**Core Concept**
Growth-restricted fetuses are at risk for various neonatal complications due to the intrauterine environment's impact on fetal development. This is primarily mediated through the placental insufficiency and altered maternal-fetal circulation, which impairs nutrient and oxygen delivery to the fetus.

**Why the Correct Answer is Right**
Growth restriction (GR) is associated with increased risks of hypoglycemia, hypocalcemia, hypothermia, and polycythemia. This is due to the fetus's adaptation to the intrauterine stress, which leads to altered metabolic pathways and increased erythropoiesis. The fetus's pancreas is less responsive to glucose, leading to poor glucose tolerance and subsequent hypoglycemia. Additionally, the increased erythropoietin levels stimulate the production of red blood cells, resulting in polycythemia. Hypocalcemia can occur due to the impaired parathyroid gland development, and hypothermia is a result of the fetus's inability to maintain its core temperature.

**Why Each Wrong Option is Incorrect**
**Option A:** Hypertension - Incorrect. Growth-restricted fetuses are more likely to have hypotension due to the decreased cardiac output and peripheral resistance.

**Option B:** Respiratory distress syndrome (RDS) - Incorrect. This option is incorrect because growth-restricted fetuses often have an increased surfactant production, which reduces the risk of RDS.

**Option C:** Polycythemia - Incorrect. This option is incorrect because it is actually a correct association with growth restriction.

**Option D:** Hypocalcemia - Incorrect. This option is incorrect because hypocalcemia is a known complication of growth restriction.

**Clinical Pearl / High-Yield Fact**
Growth-restricted fetuses are at increased risk of neonatal complications, including hypoglycemia, hypocalcemia, hypothermia, and polycythemia. It is essential to monitor these fetuses closely in the neonatal period to prevent and manage these complications.

**Correct Answer: D. Hypertension.**