Which of the following is a "Qualitative instrument" to control supply of money?

Moral suasion

The correct answer is option 2: Moral suasion

Following are the quantitative measures:

1. Bank rate
2. Repo rate
3. Reverse repo rate
4. Open market operations
5. Varying legal reserve requirements i.e. CRR, SLR

Following are the qualitative measures:

1. Imposing margin requirements
2. Moral suasion and direct action
3. Selective credit control