**Core Concept**
A horizontal fracture of the maxilla is a type of maxillofacial trauma involving a break in the bone structure of the upper jaw. This fracture can result from high-impact injuries, such as falls from a height or motor vehicle accidents.

**Why the Correct Answer is Right**
The correct answer is a Le Fort I fracture. This type of fracture is characterized by a horizontal break in the maxilla, just above the teeth, causing the upper jaw to separate from the rest of the facial skeleton. The fracture occurs due to the transmission of force from the nasal septum and the orbital floor, which leads to the detachment of the maxilla from the pterygoid plates.

**Why Each Wrong Option is Incorrect**
**Option A:** A Le Fort II fracture is characterized by a pyramidal fracture that involves the nasal bones, the orbital floor, and the maxilla. This is not a horizontal fracture of the maxilla.
**Option B:** A Le Fort III fracture is a severe type of maxillofacial trauma that involves a complete separation of the maxilla from the rest of the facial skeleton. While it does involve the maxilla, it is a more complex fracture than a horizontal fracture.
**Option C:** A zygomatico-maxillary complex (ZMC) fracture involves the zygomatic bone and the maxilla, but it is not a horizontal fracture of the maxilla.

**Clinical Pearl / High-Yield Fact**
A Le Fort I fracture is often associated with a "floating palate," where the maxilla is separated from the rest of the facial skeleton, and the palate appears to be "floating" in mid-air. This can be a key diagnostic feature on clinical examination.

**Correct Answer:** C.