**Core Concept**
Prolonged exposure to high glucose levels in pregnancy can lead to fetal hyperinsulinism and altered metabolic profiles. Babies born to diabetic mothers (DM) exhibit various metabolic disturbances due to intrauterine hyperglycemia and hyperinsulinism.

**Why the Correct Answer is Right**
Hypercalcemia is not typically associated with babies born to diabetic mothers. The correct metabolic disturbances in these babies include hypoglycemia, hypokalemia, and obesity due to the fetal overproduction of insulin in response to maternal hyperglycemia. Insulin stimulates the growth of adipose tissue and inhibits lipolysis, contributing to fetal obesity. However, hypercalcemia is not a characteristic feature of babies born to diabetic mothers.

**Why Each Wrong Option is Incorrect**
**Option B:** Hypokalemia is a common electrolyte disturbance in babies born to diabetic mothers due to the increased insulin levels, which promote potassium uptake into cells.
**Option C:** Hypoglycemia is a common feature in babies born to diabetic mothers due to the increased insulin levels, which can lead to hypoglycemia after birth.
**Option D:** Obesity is a characteristic feature in babies born to diabetic mothers due to the fetal overproduction of insulin, which stimulates the growth of adipose tissue.

**Clinical Pearl / High-Yield Fact**
Babies born to diabetic mothers are at risk of hypoglycemia due to the increased insulin levels, which can lead to seizures, coma, and even death if not promptly treated. Monitoring for hypoglycemia and administering glucose supplements as necessary is crucial in the management of these babies.

**✓ Correct Answer: A. Hypercalcemia**