Alab is conducting a test to see if people prefer cola a or cola b. the steps in the test are outlined below:
step 1. recruit one hundred volunteers and tell them the purpose of the study.
step 2. give them cola a and ask them to tell how delicious it is.
step 3. give them cola b and ask them to rate the flavor.
step 4. reveal which cola they preferred.
which step could lead to biased results?