Answer : 2. "15 अगस्त 1969 को "
Explanation :

1. Indian Space Research Organization (ISRO) is the space agency of India. This organization involves science, engineering and technology to reap the benefits of outer space for India and mankind.

2. ISRO is a major component of the Department of Space, Government of India. The department executes the Indian space program primarily through various centres or units under ISRO.

3. ISRO was earlier known as the Indian National Committee for Space Research (INCOSPAR), which was founded by Dr. Vikram A. It was established by the Government of India in 1962 on the vision of Sarabhai. ISRO was formed on August 15, 1969, and replaced INCOSPAR with an expanded role to harness space technology.

4. Antrix Corporation is the marketing arm of ISRO.

5. ISRO's Master Control Facility is located in Hassan.