The correct answer is He heard loud noises and was curious.
Explanation:
As soon as Henry was walking through the forest, a great rumble surprised him from a distance. The whole set of sounds he began to hear left him paralyzed.
At that moment, Henry starts running towards the battle.
He thought: <em>"if the earth and the moon were about to clash, many persons could doubtless plan to get upon the roofs to witness the collision."</em> This demonstrates the great curiosity he felt for what he was hearing, and that was the reason he returned.
In chapter 8 of the Red Badge of Courage, the thing that caused Henry to turn back to the frontline after fleeing is that He heard loud noises and was curious.
