Read the excerpt from "The Arming of Patroclus." So the warriors went to battle in close array, helmet to helmet and shield to shield, close as the stones with which a builder makes a wall.

What is the meaning of the figurative phrase "close as the stones with which a builder makes a wall" as it is used in the text?

The warriors' armor resembles stones.

The warriors march very closely to one another.

The warriors get very close to their enemy.

The warriors' armor is incapable of being pierced. .