Psychologist Davis Strayer Wanted to Find Out If Using a Cell

Psychologist Davis Strayer wanted to find out if using a cell phone while driving a car affected the likelihood of having an accident.First,he formed two groups of people and gave members of one group a test of driving ability while they were using a cell phone with the second group taking the driving test without using a cell phone.He confirmed that almost all drivers talking on cell phones drive no better than people who are legally drunk and are more likely to have an accident.In his study,Dr.Strayer used

A) naturalistic observation.
B) the experimental method.
C) the survey method.
D) a correlational study.