Design B: A study is being done to test the effects of three different types of supplements to determine which is the most effective at lowering cholesterol levels. Three blocks are set up where one block is set up for each supplement. The subjects are randomly assigned to the blocks. Once the subjects are in the blocks, each person within the block takes their assigned pill for three months, then their cholesterol levels are tested. The cholesterol levels are compared to the original cholesterol readings, cholesterol levels are compared within each block, and finally all cholesterol levels are compared. A common mistake is to think that Design B is an experiment done using a randomized block design. Explain why Design B fails the randomized block design