Answer:
c) Scientific reasoning
Explanation:
Piaget's pendulum task consists in determining which factor is most important in determining the speed of swing of the pendulum, given a set of strings and a set of weights.
Participants in this task had to consider the following factors:
To determine which factor was the key factor in determining the speed of swing, they have to use the experimental method (they need to vary one variable at a time)
This systematic approach is an indication that children and adolescents are thinking logically.
Thus, since they need to use an experimental method and a systematic approach we can conclude that the right answer is c) scientific reasoning.
