Step 1: Importance of political parties.
Political parties are essential for the functioning of democracy. They contest elections, form governments, represent public opinion, and provide a link between people and the government.
Step 2: Options analysis.
(A) Local self government: Important, but not termed as lifeline.
(B) Political parties: Correct — they are called the lifeline of democracy.
(C) Fundamental Rights: Basic for individuals, but not the lifeline of democratic process.
(D) Directive Principles: Guidelines for governance, not lifeline.
Step 3: Conclusion.
Thus, Political parties are the lifeline of democracy.