Dr. Branch would like to study the relationship between room lighting and college students' test performance. He randomly assigns students to one of two groups. The first group takes an exam in a dimly lit room;the second group takes the same exam in a regularly lit room.Which is the experimental group? the group of students who were randomly assigned to one of the two conditions the group of students who took the exam in the dimly lit room the group of students who took the exam in the regularly lit room There is no experimental group because this is a naturalistic observation research design.