Answer:
5
Step-by-step explanation:
When calculating participants in a factorial design research study always look at the number of conditions or treatment conditions. The reason is that for each condition, the two variables or factors will be analysed at different levels. Here, factor A has two levels and factor B has three levels. Therefore, for each condition at least one participant will be tested against the two levels of factor A and three levels of factor B. Since, 5 treatment conditions are considered hence, 5 participants are required.