Laws that protect the confidentiality of key interview subjects and reporters' rights not to have to reveal the sources of controversial information used in news stories are called.

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.        

can you tell me where are the ansawer choices

can you explain a little further maybe give multiple choice? ?