Step 1: Concept of direct democracy.
Direct democracy = Citizens directly participate in decision-making (through referendums, initiatives).
Step 2: Analyze options.
(A) Switzerland – Correct, it practices direct democracy through frequent referendums.
(B) India – Representative democracy (citizens elect representatives).
(C) America – Representative democracy.
(D) Belgium – Federal representative system, not direct.
Step 3: Conclusion.
Correct answer: (A) Switzerland.