Answer:
Five reasons ranked, why India would be attractive.
1. Very large population since ancient times - this simply means: more people to extract taxes from, since the main goal of an empire is to conquer many lands and ethnicities, in order to take economic resources from them.
2. Strategic geographic location - India has access to both sides of the Indian Ocean, and it can connect the Middle East with Southeast Asia, this is very important for trade.
3. Central location for trade - as said before, India is almost in the middle of Asia, and it is a central place for many trade routes between East Asia, the Middle East, and Europe.
4. For defensive purposes - a neighboring country may feel that India is a threat, and decide to simply conquer it.
5. Prestige - India was an ancient, diverse culture, and ruling India, being the Emperor of India, will always be a prestigious position.
3. Explain which reason you think was most important and why you think that.
The most important reason is the large population. India has been one of the most populated countries since anciet times because the land is very fertile. More people = more taxes, and the main goal of an empire is to take taxes from the people that it rules.