Explanation:

Disinvestment means the dilution of the stake of the Government in a public enterprise. Strategic disinvestment is transferring the ownership and control of a public sector entity to some other entity (mostly to a private sector entity). Unlike the simple disinvestment, strategic sale implies some sort of privatization.
• The Department of Investment and Public Asset Management (DIPAM) under the Ministry of Finance has been made the nodal department for the strategic stake sale in the Public Sector Undertakings (PSUs). Hence statement 1 is not correct.
• Types of Disinvestments are:

• Disinvestment through minority stake sale: While pursuing disinvestment through minority stake sale in listed CPSEs, the Government will retain majority shareholding, i.e. at least 51 percent of the shareholding and management control of the Public Sector Undertakings. The Department of Investment and Public Asset Management (DIPAM) is to identify CPSEs in consultation with respective administrative Ministries and submit a proposal to Government in cases requiring Offer for Sale of Government equity.
• Strategic Disinvestment: It is to be undertaken through a consultation process among different Ministries/Departments, including NITI Aayog. NITI Aayog identifies CPSEs for strategic disinvestment and advises on the mode of sale, percentage of shares to be sold of the CPSE and method for valuation of the CPSE. Hence statement 2 is correct.

Disinvestment proceeds in the last 5 years.
Year                 Disinvestment proceeds
2014-15            24,277.17
2015-16            23,996.80
2016-17            34,938.68
2017-18            57,273.05
2018-19            62,883.20

• From the above table, it is clear that Disinvestment proceeds though increased but there was no steady pattern in its growth in the last 5 years. Hence statement 3 is not correct.
• Hence option a is the correct answer.