Answer: D) It depicts how the Kiowas are connected to the land and traveling.
Step-by-step explanation: In the given excerpt about the Kiowas, we can see that they are summer people, they don't travel when the weather is cold, but when the summer arrive they start to travel, because they love to do that. This passage develops the central idea by explaining how the Kiowas are connected to the land and traveling ("but when the season turns and the land becomes warm and vital they cannot hold still").