Explanation:

• The FDI Policy prohibits retail trading in any form through e-commerce for companies with FDI engaging in the activities of multi-brand retail trading. Multi-brand retail trading means selling different products of various brands through one platform. India has not allowed FDI in inventory-driven models of e-commerce.

• The inventory model, which Walmart and Amazon use in the United States, is where the goods and services are owned by an e-commerce firm that sells directly to retail customers. The restriction aims to protect India's vast unorganized retail sector that does not have the clout to purchase at scale and offer big discounts. 

• India amended its FDI policy in e-commerce marketplaces in 2018 to classify any vendor accounting for more than 25% of the platform’s total sales as "controlled" by the marketplace operator. So, no seller must exceed 25 per cent of the total business on any foreign e-commerce platform. 

Hence option 2nd is correct.