The correct answer is: Both (A) and (R) are true, but (R) is not the correct explanation of (A).
Assertion (A) is true. In 1991, the Indian government announced a series of economic reforms, known as the New Economic Policy (NEP). One of the key reforms was the liberalization of foreign investment. The NEP allowed foreign companies to invest in India without any restrictions, except in a few sensitive sectors.
Reason (R) is also true. The government did enhance the investment limit of small scale industrial units in 1991. However, this was not the reason for the liberalization of foreign investment. The liberalization of foreign investment was done to attract foreign capital and technology into India, and to boost economic growth.
Therefore, both (A) and (R) are true, but (R) is not the correct explanation of (A).