is the standard deviation of a sampling distribution.

is the standard deviation of a sampling distribution. Options: (a) Standard error (b) Sample standard deviation (c) Replication error (d) Meta error ✅ Correct Option: (a) Standard error Explanation (200+ words): The standard error is defined as the standard deviation of a sampling distribution, reflecting variability across samples. 10 PPSC-Related Facts: 1. Measures sampling variability 2. Used in inference 3. Different from SD 4. Decreases with large samples 5. Used in CI 6. Used in tests 7. Theoretical concept 8. Depends on population SD 9. Key exam concept 10. Core statistical measure