Answer:
The sentence that shows the theme is:
"will you chuck me your bullwhip here ashore? Then horses is getting kind of a dozey."
Explanation:
"Water Never Hurt A Man" by 'Walter Edmond' says that pain and suffering are a part of one's growing up. One learns to overcome his fears and hardships and become stronger in life.
In Option 4, the line shows that John is a changed boy and is no longer scared of his father and thinks his father would not be angry if he asks for his whip as he has dropped them. John has now matured and conquered his fear.
Other options do not show that conquering fears makes one stronger.