Find out the correct definition of different scholars on party systems
A. Modern democracy is a party democracy (Katz)
B. Democracy is unthinkable save in terms of parties(Schumpeter)
C. Parties are the core institutions of democratic politics(Lipset)
D. The existence of political parties Is often as a necessary condition for the existence of modern democracy( Robert Dahl).

Correct option is D

A. Modern democracy is a party democracy (Katz): This statement by Katz emphasizes the essential role of political parties in modern democratic systems.
C. Parties are the core institutions of democratic politics (Lipset): Lipset's definition highlights the centrality of political parties in democratic governance.