Explanation:

- Option 1: 1990

- 1990 was a year of economic challenges for India, but no major reform package was introduced.

- Option 2: 1991

- This is the correct answer. In 1991, India faced a balance of payments crisis. The government introduced several economic reforms aiming at liberalization, privatization, and globalization to open up the economy.

- Option 3: 1993

- By 1993, the reforms initiated in 1991 were in the process of being implemented, but no new major package was introduced this year.

- Option 4: 1995

- In 1995, reform processes continued, especially in areas like trade and financial services, but this was not the start year.