<em>Structure and Function of ArthropodsArthropods range in length from about 1 millimeter to 4 meters (about 13 feet). They have a segmented body with a hard exoskeleton. They also have jointed appendages. The body segments are the head, thorax, and abdomen. </em><span><em> In some arthropods, the head and thorax are joined together as a cephalothorax.</em></span>
Its quite difficult to understand the question
D is the answer because I had to answer the same question
A group of organs would be an organ system so perhaps B
