In a partnership, each partner operates as both a principal and an agent. This duality implies:
A partner is obligated by the actions of their co-partners (as a principal).
A partner can commit the firm to obligations through their own business-related actions (as an agent).
This concept is referred to as the principle of mutual agency, a cornerstone of partnership. Consequently:
Assertion (A) is accurate.
Reason (R) is also accurate and adequately elucidates the foundation of Assertion (A).
Therefore, option (1) is the correct selection.