Answer :
Scientists were interested in testing a new technique to prevent slipping on ice one group simply wore boots, while the other group wore socks over their boots.
Option: C
Explanation:
Scientist always try to bring out a new technique to solve out some problems like to prevent or avoid slipping on ice scientist followed a method that is they divide the whole group into two sub parts one having simple boots while other group having socks over boots.
In this way scientist want to watch and experiment the effect of not wearing boots and having boots with socks that affect the slipping over ice. If both the groups wore same shoes then the experiment would not work out properly. Two different techniques must be followed by the scientist.