Final answer:
The Stegosaurus's plates likely served to help control body temperature and as display structures for attraction or intimidation, potentially changing colour by blood flow.
Step-by-step explanation:
The Stegosaurus is well known for the distinctive plates along its back. While their exact function is debated, the most widely accepted theories suggest that these plates served two main purposes: b. to control body temperature and c. as display structures, which could change colour due to blood flow. It is thought that the plates could help regulate the body temperature of the Stegosaurus, similar to how modern reptiles manage their temperature through their environment. Additionally, the plates could have been used for display purposes, either for attracting mates or intimidating other animals, with the ability to flush with blood potentially allowing them to change colour.