A group of college students believes that herbal tea has remarkable restorative powers. To test their theory, they make weekly visits to a local nursing home, visiting with residents, talking with them, and serving them herbal tea. After several months, many of the residents are more cheerful and healthy. (a) The explanatory variable in this experiment is .A. A. herbal tea. .A. B. visits of the college students. .A' C. the fact that this is a local nursing home. .A. D. the emotional state of the residents. (b) Which of the following may be correctly concluded from this study? A A. There is some evidence that herbal tea may improve one's emotional state. The results would be completely convincing if a scientist had conducted the study rather than a group of college students. A B. The results of the study are not convincing because only a local nursing home was used and only for a few months. .A. c. Herbal tea does improve one's emotional state, at least for the residents of nursing homes. .A. D. The results of the study are not convincing because the effect of herbal tea is confounded with several other factors. (0) The lurking variable in this experiment is A A. herbal tea. .A. B. the fact that this is a local nursing home. .A. C. the emotional state of the residents. A D. visits of the college students. Note: You can earn partial credit on this problem. AH in l' III in 1