Detect and count all possible combinations across a dataset with three columns

Question

I have a data set that has 3 columns , (ID , D , AE).

sample=data.frame(
  ID=c(1,1,1,1,2,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5),
  D=c(\'a\',\'b\',\'c\',\'d\',\'e\',\'f\