A healthy-eating program requires participants to eat a large amount of fruits and vegetables. In the first phase, the researcher observes the participants while they eat their normal diet. In the next phase, the researcher adds fruits, then adds vegetables in the following phase. After making the appropriate levels of observations, the researcher returns the participants to the baseline phase and then repeats the process of adding first fruits and then adding vegetables as well. Which research design is this researcher using?

a. ABAB design
b. multiple-baseline design
c. alternating-treatments design
d. changing-criterion design
e. Component-analysis design

Ans: e. Component-analysis design