The University of Michigan Health and Retirement Study (HRS) surveys more than 22,000 Americans over the age of 50 every two years. A subsample of the Health and Retirement Study (HRS) participated in the 2009 Internetbased survey that collected information on a number of topical areas, including health (physical and mental, health behaviors); psychosocial items; economics (income, assets, expectations, and consumption); and retirement. Two of the questions asked on the Internet survey were, "Would you say your health is excellent, very good, good, fair, or poor?" and "Do you smoke cigarettes now?" A twoway table of the results is given:

	Current Smoker
Yes	No
Excellent	25	484
Very Good	115	1557
Good	145	1309
Fair	90	545
Poor	29	11

The null hypothesis for the chisquare test for this twoway table is

A. the distributions of health rating are the same for smokers and nonsmokers.

B. the distributions of health rating are worse for smokers and nonsmokers.

C. the distributions of health rating are better for smokers and nonsmokers.

D. smokers rate their health worse than nonsmokers.