Use the Following Information for Questions

Multiple Choice

Use the following information for questions:
How old are babies when they learn how to crawl? Does it take longer in the winter months because of all the bulky clothes? Data was collected at various pediatricians' offices. Parents indicated how old (in weeks) their baby was when they first started crawling (not scooting on the belly) . Data for babies born in January, May and September is displayed below.
-The researcher has elected to conduct a nonparametric Kruskal-Wallis test to analyze the results. What would be the correct null hypothesis for this test?

A) The sample means are equal for the three age groups.
B) The population medians for the three age groups all differ.
C) The sample medians are equal for the three age groups.
D) The population medians are equal for the three age groups.