Which of the Following Best Describes the Approach Taken If $e _ { i }$

Multiple Choice

Which of the following best describes the approach taken if the expected frequency $e _ { i }$ for any cell i is less than 5?

A) We must choose another sample of five or more observations.
B) We should use the normal distribution instead of the chi-squared distribution.
C) We should combine the cells such that each observed frequency $f _ { i }$ is 5 or more.
D) We must increase the number of degrees of freedom for the test by 5.