"Childhood vaccinations: In January 2015, the Pew Research Center reported results from one of their surveys. "Asked about whether vaccines for childhood diseases such as measles, mumps, rubella (MMR) and polio should be required or left up to parental choice, 68% of adults say such vaccines should be required while 30% say that parents should be able to decide whether or not to vaccinate their children."

The following is an excerpt from the press release:

The survey of the general public was conducted using a probability-based sample of the adult population by landline and cellular telephone Aug. 15-25, 2014, with a representative sample of 2,002 adults nationwide. The margin of sampling error for results based on all adults is plus or minus 3.1 percentage points.

C. Funk and L. Raine. Public and Scientists’ Views on Science and Society (2015) http://www. pewinternet. org/2015/01/29/chapter-3-attitudes- and-beliefs-on-science-and-technolo gy-topics/#vaccines-and-access-to-e xperimental-treatments-18-point-gap

Which of the following statements is correct when interpreting the 95% confidence interval for these findings?

a. We are 95% confident that 68% of American adults say that vaccines for childhood diseases such as measles, mumps, rubella (MMR) and polio should be required.
b. We are 95% confident that between 64.9% and 71.1% of American adults say that vaccines for childhood diseases such as measles, mumps, rubella (MMR) and polio should be required.
c. We are confident that 95% of the 2,002 American adults in the sample say that vaccines for childhood diseases such as measles, mumps, rubella (MMR) and polio should be required.
We are 95% confident that between 62.6% and 74.2% of American adults say that vaccines for childhood diseases such as measles, mumps, rubella (MMR) and polio should be required."