Read the following passage, and select a suitable word for each blank from the word bank. Write the corresponding letter for each item in the blank. Last summer, Derek completed a research project for his psychology thesis. He was studying child behavior and wanted to _______ (1) bad behavior back to its source. Derek took children of different ages and put them in a(n) _________ (2)empty room, there were only a few toys and a small _______ (3) to lie down on. He then presented them with different stimuli that they might encounter during the day. For example, he would play music at a loud or soft _________ (4) , adjust the lighting to be very bright or very dim, or fill the room with different smells, both good and bad. He had a(n) _________ (5) of several hundred _________ (6) stimuli. It was interesting to watch the children's behavior ______ (7) in response to the changing environment. Nearly all children eventually displayed some form of ________ (8) behavior, but some of them created a serious ________ (9) in the room and had to be removed. The reactions were all fascinating and Derek recorded everything that happened. He is now trying to ________ (10) the meaning of these results and the implications for child behavior. Hopefully, his work will help clarify and identify potential sources of misbehavior. A. unfold B. retrieve C. trace D. disturbance E. comprehend F. distinct G. repertoire H. diverge I. naughty J. catalog K. gush L. mostly M. guy N. couch O. volume