**Core Concept**
High-risk babies are those born with conditions that increase the likelihood of morbidity or mortality. These conditions can be due to maternal, fetal, or perinatal factors. Identifying high-risk babies is crucial for providing appropriate prenatal care, intrapartum monitoring, and postnatal management.

**Why the Correct Answer is Right**
To determine high-risk babies, healthcare providers assess various factors such as gestational age, birth weight, presence of congenital anomalies, and maternal medical conditions. Babies born prematurely (before 37 weeks of gestation) or with low birth weight (<2500 grams) are at a higher risk for complications. Additionally, congenital anomalies, such as heart defects or chromosomal abnormalities, can also classify a baby as high-risk. **Why Each Wrong Option is Incorrect** **Option A:** Gestational diabetes mellitus (GDM) is a risk factor for high-risk babies. GDM can lead to macrosomia, preterm labor, and increased risk of congenital anomalies. **Option B:** Maternal hypertension is a risk factor for high-risk babies. Uncontrolled hypertension can lead to placental insufficiency, growth restriction, and preterm labor. **Option C:** This option is not provided. **Clinical Pearl / High-Yield Fact** A mnemonic to remember common risk factors for high-risk babies is "BIRTH": **B**irth weight <2500 grams, **I**ncidental or suspected congenital anomalies, **R**isk factors in the mother (e.g., diabetes, hypertension), **T**ransfusion or bleeding during pregnancy, and **H**istory of previous stillbirth or perinatal loss. **Correct Answer: D.**