Increasing the sample size of an opinion poll will reduce the
(a) bias of the estimates made from the data collected in the poll.
(b) variability of the estimates made from the data collected in the poll.
(c) effect of nonresponse on the poll.
(d) variability of opinions in the sample.
(e) variability of opinions in the population.

b. variability of the estimates made from the data collected in the poll

Explanation:

A sample size tends to influence the precision of the estimates and power of the study. With the increase in the sample size of an opinion poll there is a decrease in the means of the standard deviation. This results in the reduction of the variability of the estimates which is made from the data collected in the poll. Large samples will have small margin of error.

answer; /// representative democracy restricting trade,is your correct answer;

even though you have attached neither the chart nor the generalizations, i have located them online. the right answer is d, since they are asking you about a generalization. you can only infer from the chart that between 2008 and 2009 the number of employed workers decreased significantly (from over 115 millions to 107 millions approximately), which signals some type of economic crisis.