Final answer:
Alex will be using the somatic nervous system to kick the soccer ball, as this system controls voluntary movements like kicking.
Step-by-step explanation:
When Alex sees a soccer ball coming his way and wants to kick the ball into the goal, he will be using the somatic nervous system. This part of the nervous system is responsible for voluntary movements, such as kicking a ball. The central nervous system (comprising of the brain and spinal cord) will process the visual information and initiate a motor response, but the actual movement control and execution involve the somatic nervous system. Alex's muscles will contract in response to signals from motor neurons that originate in the central nervous system, but function within the realms of the somatic division of the peripheral nervous system.