Question: NAME_1 presents one group of shoppers with an advertisement for milk that is 99 percent fat free and another group of shoppers with an advertisement for milk that is 1 percent fat. What is NAME_1 most likely testing?
A: representativeness heuristic
B: confirmation bias
C: schema
D: framing
Please eliminate two incorrect options first, then think it step by step and choose the most proper one option.