1. Assertion (A): The origin of feudal system in ancient India can be traced to military campaigns. 2. Reason (R): There was considerable expansion of the feudal system during the Gupta period.

1. Assertion (A) is true. The practice of granting land or revenue in lieu of cash salaries, particularly to military personnel or officials, is seen as a key factor in the origin of feudal tendencies in ancient India, often linked to the needs of maintaining armies during military campaigns. 2. Reason (R) is also true. The Gupta period witnessed a significant increase and formalization of land grants (agrahara, brahmadeya, grants to officials), which contributed to the expansion of the feudal system or quasi-feudal structures. 3. However, the expansion during the Gupta period (R) describes a later development phase, not the initial origin linked to military necessities (A). While related, R does not fully explain the origin mentioned in A. Thus, R is not the correct explanation of A.