Step 1: Understanding the Companies Act.
As per the Companies Act, 2013, the maximum number of partners in a partnership firm is not limited. There is no upper cap on the number of partners in a partnership firm.
Step 2: Analysis of other options.
(A) 20: Incorrect. This is the limit for a partnership firm in certain cases under the old laws.
(B) 50: Incorrect. This is the limit for certain types of firms in some jurisdictions, but not as per the Companies Act, 2013.
(C) 100: Incorrect. The number of partners is not capped under the Companies Act, 2013.
(D) No limit: Correct. As per the Companies Act, 2013, there is no limit on the number of partners in a partnership firm.
Step 3: Conclusion.
Therefore, the correct answer is that there is no limit on the number of partners.
Final Answer:} No limit.