Explanation:

Marriage by purchase is called:

- Arsha marriage (Option 1): This involves giving a token gift (usually cows) to the bride’s family by the groom, not purchasing the bride.

- Asur marriage (Option 2): In this type, the groom gives wealth to the bride’s family, almost like a purchase. It is considered less respectable. (Correct Answer)

- Rakshas marriage (Option 3): This is by force or abduction, not by purchase.

- Paishach marriage (Option 4): This involves seduction or taking advantage of the bride when she is unaware—also not related to purchase.

Correct Answer: Option 2 - Asur marriage