Detailed Solution:

The correct answer is “Narmada Valley”.

The earliest evidence of Homo erectus (an early human ancestor) in India has been found in the Narmada Valley (in present-day Madhya Pradesh).

A partial human skull discovered near Hathnora (in the Narmada region) is considered to be one of the oldest fossil records of early humans in the Indian subcontinent. This fossil is dated to be around 2,50,000 to 5,00,000 years old, belonging to the Middle Pleistocene period.