Answer:
Within subject (repeated measures)
Step-by-step explanation:
Within subjects design means same participants provide data for one or more groups. It is having all the subjects participate in both levels of the independent variable. (the experimental group and the control group). The merit of within subjects design is that it increases efficiency in data collection; fewer participants, no need for extra control group like between subjects need, Increases validity; participants may approach tasks in different ways, increased statistical sensitivity, reduces extraneous variables and others. A demerit of within subjects designs is learning effects (ambiguous figures; once seen won't forget cannot run same subjects in both groups) , order effects, mutually exclusive groups.