Answer :
The first answer is a letter c - normal distribution. The normal distribution is the most significant and most generally used distribution in statistics. It is also known as the Gaussian or standard normal distribution, is the probability distribution that plots all of its values in an even fashion, and most of the results are positioned around the probability's mean. Values are equally likely to plot either above or below the mean. And the second answer is letter d - sampling distribution. In statistics, it is the probability distribution of a given statistic centered on a random sample. Sampling distributions are significant in statistics because they deliver a major simplification to the statistical inference.