One of these is not a social development under colonial rule.

Exploitation is not a social development under colonial rule. Under colonial rule, exploitation was a means for the colonizers to extract resources and labor from the colonized people. This often led to the oppression and marginalization of the colonized people, rather than a social development. Trade relations, the establishment of a common legal system, and the emergence of the press are all social developments that occurred under colonial rule. Trade relations led to the exchange of goods and ideas between different regions and cultures, while the establishment of a common legal system provided a framework for resolving disputes and enforcing laws. The emergence of the press allowed for the dissemination of information and the formation of public opinion.