Why has the government taken up the responsibility

Why has the government taken up the responsibility of public sector activities in a country like India? Explain any three reasons.

There are various reasons due to.which government has taken up the responsibility of public sector.
Three reasons with example of public sector activities are
(i) Railways :Only the government can invest large sums of money on projects with a long gestation ’ period.
(ii) All India Institute of Medical Sciences (AIIMS): It provides quality health services at economical rates.
(iii) National Thermal Power Corporation (NTPC): To provide electricity at a lower cost rate was the main objective of the government, to protect and encourage the small scale industries also included in purpose.