What is PIL?how does this help people?

In simple terms, a PIL is a petition that an individual or a non-government organisation or citizen groups, can file in the court seeking justice in an issue that has a larger public interest. It aims at giving common people an access to the judiciary to obtain legal redress for a greater cause

this null effect is caused by a weak manipulation and ineffective internal validity. in a scientific study, as the one dr. morimoto is trying to perfom, internal validity refers to the confidence placed in the cause-effect relationship and to how well an experiment is done and able to eliminate confounding variables.        

answer; i believe the correct answer is (117);