A scientist wants to determine the effect of two types of insulin (A, B) and diets containing one of the three substances: aspartame, sugar and saccharin on the glucose level of rats. Eighteen cages, each containing four rats, are used in the experiment. The cages are arranged in three tables in two rows of three cages stacked on top of one another. For each table, the scientist randomly assigns one of the three diets to stack (column) of two cages. He also administers at random, each insulin type to one of the two rows of cages. The average glucose level of rats per cage was measured after 5 hours. Which of the following is (are) TRUE?

A. The standard error of difference between two insulin means is expected to be less than the standard error of difference between two diet means

B. The standard error of difference between two insulin means at the same level of diet is expected to be less than the standard error of difference between the overall means of two insulin

C. The standard error of difference between two insulin means is expected to be equivalent to the standard error of difference between two diet means

B. The standard error of difference between two insulin means at the same level of diet is expected to be greater than the standard error of difference between the overall means of two diets