- Statement I is correct: The Representation of the People Act, 1951, specifically Part IV A (Sections 29A to 29C), provides for the registration of associations as political parties. - Statement II is correct: Section 29A of the RPA, 1951, mandates that any association seeking to be registered as a political party must apply to the Election Commission of India. The ECI is the registering authority. - Statement III is correct: At the time this question was framed (likely around 2000-2001), one of the primary criteria for a political party to be recognised as a 'National Party' by the Election Commission was its recognition as a State Party in at least four or more States. Other criteria also existed, but this was a valid and common pathway to national status. - Statement IV is correct: While precise historical numbers can vary slightly depending on classification changes or timing, records for the 1999 General Elections show a number of recognised National and State parties that align closely with these figures. ECI data indicates around 7 National Parties and over 50 State Parties recognised around that time, making the statement (6 National and 48 State) historically accurate within reasonable approximation for an MCQ.