Answer:
d. A person to an automobile.
Step-by-step explanation:
I thought of this like an analogy, where two things are compared to each other. But "a sidewalk to the sea" and "a skateboard to a boat" didn't make a lot of sense, so I used the process of elimination and figured it wasn't either of those answers. The answer that is probably correct is either "a sailor to a sailboat" or "a person to an automobile". I ruled out "a sailor to a sailboat" because a sailor is the person driving the boat, and doesn't really compare with the metaphor "the sidewalk racer".
I hope this helps and I gave an okay answer!! Have a wonderful day ^-^