Which of the following statements about the analysis of two-way tables is/are TRUE?

A) Under the null hypothesis,the expected cell count is = .
B) In a table with r rows and c columns,the number of degrees of freedom is (r - 1) (c - 1) .
C) A possible null hypothesis is that there is no association between the row and column variables.
D) All of the above are true.
E) Only A and B are true.

All of the statements are true. Statement A is true because under the null hypothesis, the expected cell count for each cell can be calculated as the product of the row total, column total, and overall total divided by the grand total. Statement B is true because the number of degrees of freedom in a two-way table is equal to (r-1)(c-1) where r is the number of rows and c is the number of columns. Statement C is true because one possible null hypothesis is that there is no association between the row and column variables, which means that the distribution of the column variable is identical across each row of the table.