Lauren, a social psychologist, hypothesizes that the best way for a young woman to increase the number of friends she has on a social networking site is to place a smiling display picture in her profile. Lauren wants to establish a cause-effect relationship between these two variables. In order to accomplish her objective, Lauren should use

The correct answer is experimental research

Explanation: Experimental research is the most prestigious design in scientific circles. It consists essentially of determining an object of study, selecting the variables capable of influencing it and defining the forms of control and observation of the effects that the variable produces on the object.

answer/// constitutional amendment;