In an experiment, psychological researchers seek to establish a cause-and-effect relationship between two types of variables by manipulating the __________ variable and measuring the __________ variable

A friend is worried that her 4-year-old daughter is not developing on schedule. What can you tell her about the physical development of preschoolers?

What will be an ideal response?

Before beginning a study on the health effects of obesity, a group of researchers agree that, for the purposes of their research, anyone with a Body Mass Index greater than 30 kg/m² will be considered obese. This is an example of _______________

A) a confounding variable B) an operational definition C) convenience sampling D) an appeal to common sense