Correct Option
The decline of the Roman Empire from the third century AD, as indicated by the question, significantly disrupted established trade routes with the West. This necessitated Indian merchants to seek alternative markets and sources for goods. South-East Asia emerged as a primary focus due to its rich resources, including spices, precious metals, and other luxury items, which were in high demand. This shift was facilitated by well-developed maritime trade networks, with various Indian kingdoms actively participating and promoting these exchanges.
Incorrect Options
African trade: While trade relations with East African regions existed, they did not become the dominant alternative for Indian merchants to the same extent as South-East Asia following the disruption of Roman trade.
West European trade: The premise of the question directly links the decline of the Roman Empire to the disruption of trade with Europe. Therefore, West European trade diminished rather than increased as a reliance for Indian merchants during this period.
Middle-Eastern trade: Trade with the Middle East was a continuous and important aspect of Indian commerce. However, in the context of finding a new primary focus after the Roman decline, South-East Asia offered a more expansive and lucrative avenue for diversification, particularly for luxury goods and spices.