A. This is an inferential study. A study using descriptive statistics creates graphs, calculations or tables to describe the population. A study using inferential statistics forms estimates, conclusions and predictions about a population based on a sample of data taken from the population under study.
B. In this example, the study used the opinion of U.S adults in relation to evolution, to establish its theory that support for Darwinism increases with the level of education. The population is the entire human population and the sample is U.S adults.