In cooperation with researchers from Cornell University, Facebook randomly selected almost 700,000 users for an experiment in "emotional contagion." Users news feeds were manipulated (without their knowledge) to selectively show postings from their friends that were either more positive or more negative in tone, and the emotional tone of their own subsequent postings was a measured. The researchers found evidence that people who read emotionally negative postings were more likely to post messages with a negative tone and those reading positive messages were more likely to post messages with a positive tone. The research was widely criticized for being unethical Explain why. Select all that apply. The Facebook users were not randomly assigned to treatment groups. The Facebook users involved in the study did not know that they were going to be subjected to treatments. This was not a double-blind experiment. The Facebook users did not provide informed consent before the study was conducted