The correct answer is option 4: More privileges should be given to Khuts and Muqadd-ams. Alauddin Khalji, the ruler during the Delhi Sultanate, implemented various measures to control black-marketing and hoarding. These measures included:

1. Collecting land revenue in kind: This means that the revenue was collected in the form of agricultural produce, rather than in currency.

2. Mandating that cultivators sell their harvested crops on the field only: This prevented hoarding and ensured that the crops were sold in a transparent manner.

3. Requiring merchants to sell all commodities in the open: This aimed to prevent black-marketing and ensure fair prices for goods.

However, giving more privileges to Khuts and Muqadd-ams, who were tax collectors, would not have directly addressed black-marketing and hoarding. It is important to note that while the provided answer is generally correct, an alternative explanation could be that the correct option was not provided.