In 2005,20%of all U.S. adults said that they had confidence in the U.S. Congress to work in the best interest of the people of the United States. Suppose that in 2015,in a random sample of145U.S. adults,21reported that they had confidence in the U.S. Congress to work in the best interest of the people of the United States.

Does the sample provide evidence that the proportion of U.S. adults in 2015 who hold this view has decreased since 2005? Test this claim at the 5% significance level.

Letpbe the proportion of U.S. adults in 2015 who have confidence in the U.S. Congress.

What conclusion below is appropriate?

At the 5% significance level, we should conclude that the proportion of U.S. adults in 2015 who have confidence in Congress is 0.20.

At the 5% significance level, we should conclude that the proportion of U.S. adults in 2015 who have confidence in Congress is 0.14.

At the 5% significance level, we should conclude that the proportion of U.S. adults in 2015 who have confidence in Congress is less than 0.20.