The correct answer is C. With the registrar of companies.
The registrar of companies is a government official who is responsible for registering companies and keeping records of their ownership. When a share is transferred, the transfer must be registered with the registrar of companies in order to be valid.
Option A is incorrect because the agency is not a government body and is not responsible for registering shares.
Option B is incorrect because the company is not responsible for registering shares. The company is responsible for keeping records of its shareholders, but it is the registrar of companies who is responsible for registering transfers of shares.
Option D is incorrect because the central government is not responsible for registering shares. The central government is responsible for setting laws and regulations governing companies, but it is the registrar of companies who is responsible for registering transfers of shares.