The correct answer is option 'D', which states that the rules committee in the Rajya Sabha consists of 16 members including the chairman. Let's understand the role and composition of the rules committee in the Rajya Sabha in detail.

Role of the Rules Committee in the Rajya Sabha:
- The Rajya Sabha is the upper house of the Parliament of India, and it has its own set of rules and procedures to conduct its business effectively.
- The rules committee is responsible for formulating and recommending changes to the rules and procedures of the Rajya Sabha.
- It plays a crucial role in ensuring the smooth functioning of the Rajya Sabha by reviewing, revising, and updating the rules as per the changing needs and requirements.

Composition of the Rules Committee in the Rajya Sabha:
- The rules committee consists of members who are elected by the Rajya Sabha itself.
- According to the current composition, the rules committee consists of 16 members, including the chairman.
- The chairman of the Rajya Sabha, who is the Vice President of India, serves as the ex-officio chairman of the rules committee.
- The remaining 15 members of the committee are nominated by the Chairman of the Rajya Sabha.
- These members are selected based on their experience, expertise, and representation from various political parties and groups in the Rajya Sabha.
- The members of the committee are usually senior and experienced parliamentarians who have a good understanding of the functioning and procedures of the Rajya Sabha.

Responsibilities of the Rules Committee in the Rajya Sabha:
- The main responsibility of the rules committee is to examine and suggest changes to the rules and procedures of the Rajya Sabha.
- It considers proposals for amending the rules and procedures brought by the Chairman of the Rajya Sabha, the Leader of the House, or any member of the Rajya Sabha.
- The committee also examines the rules and procedures of other legislatures within India and in other countries to incorporate best practices and make necessary recommendations.
- It reviews the functioning of the Rajya Sabha and suggests measures to improve its efficiency, effectiveness, and transparency.
- The committee also provides guidance and clarifications to the members of the Rajya Sabha regarding the interpretation and application of the rules and procedures.

In conclusion, the rules committee in the Rajya Sabha consists of 16 members, including the chairman. It is responsible for formulating, reviewing, and recommending changes to the rules and procedures of the Rajya Sabha to ensure its smooth functioning and effectiveness.