Answer:
3. The Sultans, following a principle outlined in the Quran, allowed Hindus to retain their faith and live within the Islamic state so long as they paid a higher tax.
Explanation:
The sultans impose the Jizya or Jizyah and even manage to do it on all level of the Hindu society (that is, including the Brahmins)
It is a per capita yearly taxation historically levied from non-Muslim subjects labeled as dhimmi according to the Quran.
Also, the dhimmi aren't allow to proselytize their religion or rise new temples.
This is an attemp to make the non-islamic society to decrease in the ladder over time as the taxes are high and either force the person to convert or to live in poverty.