This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
Confidence limit includes - 
Select and explain. 
A. Range & standard deviation, B. Median and standard error, C. Mean and standard error, D. Mode and standard deviation
C: Mean and standard error
Answer: C: Mean and standard error 
Explanation: Confidence limit

Estimate of mean varies from sample to sample.
Therefore, instead of single estimate of mean, a confidence interval generates a lower and upper limit of mean.
This interval from lower to upper limit is called confidence limit.
Confidence limit is distributed on either side of mean and the deviation from the mean is determined by standard deviation.
For example 95% confidence limit (area under 2 standard deviation) means that 95% of the values in the distribution will be included in this limit (95% confidence limit → 2 SD).
95% (2 standard deviation) is the most commonly used confidence limit.

None - in option 'c', standard error is there instead of standard deviation.
"Standard error of a statistic is the standard deviation of the sampling distribution of the statistics" . — Handbook