To Use the Wilcoxon Rank Sum Test as a Test

Multiple Choice

To use the Wilcoxon rank sum test as a test for location, you must assume that

A) the obtained data are either ranks or numerical measurements that will be converted to combined ranks.
B) both samples are randomly and independently drawn from their respective populations.
C) both underlying populations from which the samples were drawn are equivalent in shape and dispersion.
D) All the above.