Explanation:

• First statement is correct. The representatives of each State and two Union territories are elected by the elected members of the Legislative Assembly of that State and by the members of the Electoral College for that Union Territory, as the case may be, in accordance with the system of proportional representation by means of the single transferable vote.
• Second statement is correct. The Rajya Sabha election in Gujarat highlighted the procedural matrix of the ‘open ballot’ system under Rule 39AA of the Conduct of Election Rules of 1961. This says that a voter may show his/her marked ballot paper to the authorised representative of his/her political party before dropping it into the ballot box.
• Third statement is correct. The Election Commission had issued a circular in January 2014 that the provisions of NOTA be included in the Rajya Sabha elections too, after it was included as one of the options in the Electronic Voting Machines in 2013.
• From 2014onwards, biennial elections to the Rajya Sabha have been held in 16 States, and 25 bye-elections to the Rajya Sabha have been held, according to the EC circular issued on August 2, 2017. In all these elections, instructions regarding NOTA have been applicable. However, in 2018 Supreme Court has scrapped the NOTA option from the Rajya Sabha elections.
• Fourth statement is incorrect. If a voter (MLA) defies the party directive and votes for someone else or uses NOTA option, he cannot be disqualified as a legislator. But the party is free to take disciplinary action including expulsion.