WORLD CIVILIZATION

Detailed explanation-1: -Based on the fact that only one sign is displayed on the pottery surface, these examples represent a premature stage in the development of the Indus Script. Its full development was reached during the Urban period (c. 2600-1900 BCE), when longer inscriptions are recorded.

Detailed explanation-2: -Proto-Dravidian (the ancestor of all known Dravidian languages) was probly spoken by the Early Harappans, say c. 3200-2600 BCE. Its roots–which are beyond reconstruction–of course go back to the origins of human language, as is the case with any other language: every language is equally old in this sense.