Social & Preventive Medicine Children surveyed in cluster sampling for coverage of national immunization programme is: A 30 cluster of 5 children B 30 cluster of 7 children C 30 cluster of 10 children D 30 cluster of 15 children 💡 Explanation Children surveyed in cluster sampling for coverage of national immunization programme is: ✓ Correct Answer: B. 30 cluster of 7 children