The correct answer is D. all of the mentioned.
Variance and standard deviation are both measures of spread, but they are calculated differently. Variance is the average squared deviation from the mean, while standard deviation is the square root of the variance. The empirical mean is the average of the data values.
All three of these measures can be used to describe the spread of a distribution. Variance and standard deviation are more sensitive to outliers than the empirical mean. This means that they will be larger if there are a few data values that are very different from the rest of the data. The empirical mean is not as sensitive to outliers, so it is a more robust measure of spread.
Which measure of spread is most appropriate depends on the situation. If you are interested in the spread of a distribution, then variance or standard deviation would be a good choice. If you are interested in the center of a distribution, then the empirical mean would be a good choice.