In option 1, both statements A and R are considered true, with R deemed the correct explanation of A. However, this is incorrect as R focuses on expansion of the feudal system during the Gupta period, not its origin.

Option 2 is the correct answer. Here, both A and R are recognized as true but R is not the correct explanation of A. The feudal system, a hierarchical system of land-use and protection, originated in ancient India due to military campaigns but expanded through other factors, not simply the Gupta period.

Option 3 suggests statement A is true but R is false. This is erroneous because the feudal system did indeed expand during the Gupta period.

Finally, option 4 implies statement A is false and R is true. This is incorrect because the feudal system`s origin in ancient India is directly linked to military campaigns.