The correct answer is option 2, which describes the electoral system to elect the President of India as Proportional Representation and Single Transferable Vote (PR-STV) system.

Proportional Representation is a system where the seats in an elected body are allocated based on the proportion of votes received by each political party or candidate. In the case of electing the President of India, this means that the President is elected by an electoral college consisting of members of both houses of Parliament (Lok Sabha and Rajya Sabha) as well as members of State Legislative Assemblies. Each member of the electoral college has a certain number of votes, and they can cast these votes in proportion to the candidate they support.

The Single Transferable Vote (STV) system is a variant of Proportional Representation, used in many countries including India. It allows voters to rank candidates in order of preference. If a candidate does not receive enough first-preference votes to win, the candidate with the fewest votes is eliminated, and their votes are transferred to the remaining candidates based on the voters` preferences.

Therefore, the electoral system to elect the President of India involves both Proportional Representation and Single Transferable Vote system.