Answer:
The correct answer is a) distributional.
Step-by-step explanation:
The standard error is the standard deviation of the sample distribution of a sample statistic.1 The term also refers to an estimate of the standard deviation, derived from a particular sample used to compute the estimate.
The sample mean is the usual estimator of a population mean. However, different samples chosen from the same population tend in general to give different values of sample means. The standard error of the mean (that is, the error due to the estimation of the population mean from the sample means) is the standard deviation of all possible samples (of a given size) chosen from that population. In addition, the standard error of the mean can refer to an estimate of the standard deviation, calculated from a sample of data that is being analyzed at the same time.