Use the Following Situation to Answer the Next Seven Questions

Multiple Choice

Use the following situation to answer the next seven questions.
A researcher is interested in studying the effect of geographic location of grocery stores on the prices they charge for various food items. A typical "market basket" is selected and the researcher obtains data on the total basket price from 15 randomly selected stores as shown below. Note that 5 of the stores were inner city stores, 5 suburban stores and 5 campus stores.

-The degrees of freedom associated with the within-group sum-of-squares in the above problem is

A) 2.
B) 3.
C) 12.
D) 14.
E) 15.