Researchers studying the link between prenatal vitamin use and autism surveyed the mothers of a random sample of children with autism (cases) and children with typical development (controls). The table below shows the number of mothers in each group who did and did not use prenatal vitamins during the three months before pregnancy (periconception period) cross-tabulated with whether or not their child had autism.

		Autism	Typical development	Total
Periconception prenatal Vitamin use	No	111	70	181
Yes	143	159	302
	Total	254	229	483

What type of test would be most appropriate to test the hypothesis that there is no link between prenatal Vitamin use and Autism?

Select one:

a.

One-sample test of proportion

b.

Chi-square test of independence

c.

Two-sample test for difference in proportions

d.

Test for difference in sample means