Answer :
The red arrow must indicate the motion of the warm air, so the correct option is the first one.
What do the red arrows indicate?
The red arrows go from the land to the sky, so they represent a rising motion of something.
As you know, warm air is less dense than cold air, and for this reason warm air tends to rise up, in this way water vapor reaches the sky and then conforms clouds.
So what the red arrow must be indicating is the air motion, particularly, the warm air rising. So the correct option is the first one.
If you want to learn more about the water cycle, you can read:
https://brainly.com/question/2430469