Checking conditions

There are three new datasets in your environment, ds1, ds2, and ds3, that all contain two columns of categorical data. You can test the independence of the two variables for all three datasets using a permutation chi-squared test, however the chi-squared approximation method will only be accurate for one of them. Which one?

Note: since these datasets only have two columns, you can form a contingency table by simply running table() on the original data frame.