Which of the following BEST defines muscles? A. long flexible tendons that connect bones B. tough strong tissues that provide energy to perform physical activities C. thick fibrous cartilage that act when sent electrical signals D. smooth long fibers that are controlled by the skeletal system Please select the best answer from the choices provided. A B C D

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.