You are performing logistic regression in SPSS and you see a warning message that tells you that "There are 235 (13.7%) cells (i.e., dependent variable levels by subpopulations) with zero frequencies." What is this warning message trying to tell you?

a.There are some combinations of your variables that cancel each other out.

b.There are some combinations of your variables that have no observations.

c.There are some combination of your variables that produced measurements with a value of zero.

d.There are some combinations of your variables that occurred far too frequently to be accurately measured.