The correct answer is: D. The complete postal address.
The registered office clause of the memorandum of association of a company must contain the complete postal address of the registered office of the company. This address must be within the jurisdiction of the Registrar of Companies in whose state the company is incorporated. The registered office is the official address of the company and all communications to the company must be sent to this address.
Option A is incorrect because the name of the state is not required to be included in the registered office clause. Option B is incorrect because the name of the city/town is not sufficient. The complete postal address must be included. Option C is incorrect because the name of the registrar of companies is not required to be included in the registered office clause.