Final answer:
Increased foreign investment has been a major contributor to India's economic boom over the last two decades, thanks to economic reforms that reduced government control on foreign investment and trade.
Step-by-step explanation:
The economic boom in India over the past 20 years has been greatly contributed to by an increase in foreign investment. This investment has allowed for significant growth in various sectors such as information services, health care, and industrial production. By opening its markets and reducing government control on foreign investment and trade, as part of economic reforms since the 1990s, India has been able to attract substantial external investments from foreign investors. These investments are critical as they contribute to the country's capital accumulation needed to invest in physical and human capital, fostering overall economic growth.