A company can accept calls in advance, if authorised by:

The correct option is Articles of Association.

Step-by-step Explanation:

1. Understanding "Calls in Advance":
A call in advance refers to a situation where a shareholder pays a part or the entire unpaid amount on their shares to the company before the company has officially called for that payment. It represents advance payment of share capital.

2. Role of the Articles of Association (AoA):
The Articles of Association serve as the internal rulebook or constitution of a company, governing its internal management, operations, and the relationship between the company and its members. Matters related to share capital calls, forfeitures, and the acceptance of advance payments fall strictly under these internal regulations.

3. Why the Authorization is Required:
A company does not possess an inherent right to accept calls in advance. According to corporate law (such as Table F of the Companies Act), a company can only accept call money in advance if it is explicitly authorized to do so by its Articles of Association. If the Articles do not contain such a provision, the company cannot accept advance payments, nor can the Board of Directors approve it unilaterally.

4. Distinguishing from Other Options:
- Memorandum of Association: Defines the core purpose and external boundaries of the company (its relationship with the outside world), rather than internal share management details.
- Board of Directors / Shareholders: While the directors may physically exercise the power to accept the money, they can only do so if the authority is first granted to them by the Articles of Association.