Which of the following is most important when setting goals? a. working late into the night is often necessary to reach goals. b. standards should be as high as possible. c. tasks should be included but are unimportant. d. goals should be difficult but realistic.

How is the central idea developed further? (a) the author elaborates on the treatments for allergies in adults and how they work. (b) the author quotes the reactions of experts and the methods used to conduct the study. (c) the author compares the different rates of food allergies shown in children and adults. (d) the author indicates the limitations of the study because of differences in health care.