The Olmec colossal heads are giant stone sculptures representing human faces that are considered one of the earliest and most recognized examples of Olmec civilization art. These sculptures date back to the 1st millennium BCE, making them some of the oldest monumental sculptures in Mesoamerica. The correct answer, the Olmec colossal head located in La Venta, Mexico, provides a significant insight into the ancient Olmec civilization's artistic and cultural achievements.