**Core Concept:** Cephalhematoma is a condition characterized by localized swelling and discoloration of the soft tissues overlying the skull, caused by extravasation of blood into the subcutaneous tissues. It is a common finding in newborns, especially in cases of trauma, malpractice during childbirth, or congenital disorders affecting blood flow.

**Why the Correct Answer is Right:** Cephalhematoma resolves spontaneously due to the following reasons:
1. The blood gradually leaks out of the subcutaneous vessels and is absorbed by the surrounding tissues.
2. The hematoma is eventually reabsorbed by the body's immune system and fibrinolytic processes.
3. The skull gradually ossifies over time, allowing the hematoma to be absorbed by the surrounding tissues.

**Why Each Wrong Option is Incorrect:**
1. B. Option B is incorrect because the hematoma is not resolved by the baby growing out of it. The condition is self-limiting and resolves on its own.
2. C. Option C is incorrect because the swelling and discoloration are not due to increased intra-cranial pressure, which is not a primary feature of cephalhematoma.
3. D. Option D is incorrect because the condition is not caused by a pathological process, but rather, it is a normal physiological finding in newborns.

**Why Option A is Correct:**
A. The correct answer (A) states that cephalhematoma usually resolves within 2-3 weeks. This timeframe aligns with the natural history of the condition and its resolution through the processes mentioned above.

**Clinical Pearl:** Cephalhematoma is a normal finding in newborns and does not require intervention. Parents and healthcare providers should reassure families that it is a benign condition that resolves without complications in the mentioned timeframe.