The prehistoric period refers to the time before:

The invention of writing
The rise of the Mauryan Empire
The establishment of Chhattisgarh as a state
The invention of the internet

The correct answer is: The invention of writing.

The prehistoric period is the time before the invention of writing. It is a long and complex period of human history that covers the time from the first appearance of humans on Earth to the development of writing systems. The prehistoric period is divided into three main periods: the Paleolithic, the Mesolithic, and the Neolithic.

The Paleolithic period is the longest period of human history, and it covers the time from the first appearance of humans on Earth to the development of agriculture. During the Paleolithic period, humans were hunter-gatherers, and they lived in small groups.

The Mesolithic period is a short period of time that follows the Paleolithic period. During the Mesolithic period, humans began to develop agriculture, and they started to live in larger groups.

The Neolithic period is the last period of the prehistoric period, and it covers the time from the development of agriculture to the development of writing systems. During the Neolithic period, humans developed complex societies, and they began to build cities.

The invention of writing is a major turning point in human history, and it marks the end of the prehistoric period. The invention of writing allowed humans to record their history and culture, and it also allowed them to communicate with each other over long distances.

The rise of the Mauryan Empire, the establishment of Chhattisgarh as a state, and the invention of the internet are all important events in human history, but they do not mark the end of the prehistoric period.