Final answer:
Ben and Tom have a close and supportive father-son relationship as evidenced by Ben's guidance and mentorship of his son in a surfing activity.
Step-by-step explanation:
An inference that can be made about Ben's relationship with Tom is that they have a close and supportive father-son relationship. This can be supported by the details in the text which describe Ben and his son, Julian, paddling out into the ocean on surfboards. When Julian loses his balance while riding a wave, he watches his father ride the wave successfully. This implies that Ben is an experienced surfer and is able to mentor and guide his son in this activity. This suggests a positive and nurturing relationship between Ben and Tom.